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<b>reconsider </b><font color="Maroon" title="c1">FAB</font> =  <a href="funct_2.html#K1" title="FUNCT_2:func.1">Funcs</a> <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>() as  non <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>  <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a>  <b>by </b><i><a class="ref" href="funct_2.html#T11" title="FUNCT_2:th.11">FUNCT_2:11</a></i>;<br/>
<b>defpred </b><font color="Maroon">S<sub>1</sub></font>[   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ,   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ] <b>means </b>for <font color="Olive" title="b1">tv</font> being  <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()  st <font color="Olive" title="b1">tv</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> $2 holds <br/>for <font color="Olive" title="b2">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Olive" title="b1">tv</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b2">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>6</sub></font>($1,<font color="Olive" title="b2">a</font>);<br/>
<div><i><font color="Green" title="E12">A3</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_1"><b>now </b></a><div class="add"><b>let </b><font color="Maroon" title="c2">x</font> be    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="dtconstr.html#K6" title="DTCONSTR:func.6">Terminals</a> <font color="Maroon">F<sub>1</sub></font>();<br/><b>deffunc </b><font color="Maroon">H<sub>1</sub></font>(   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>()) <b>-&gt; </b>   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>3</sub></font>() = <font color="Maroon">F<sub>6</sub></font>(<font color="Maroon" title="c2">x</font>,$1);<br/><b>consider </b><font color="Maroon" title="c3">y</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()<b> such that </b><br/><a NAME="E2:25_1_1"/><i><font color="Green" title="E13">A4</font></i>: 
for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Maroon" title="c3">y</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Olive" title="b1">a</font>)
 <b>from </b><i><a class="ref" href="funct_2.html#S4" title="FUNCT_2:sch.4">FUNCT_2:sch 4</a>();<br/></i><a NAME="E3:25_1_1"/>
( <font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c3">y</font> &amp;  <a href="relset_1.html#K5" title="RELSET_1:func.5">rng</a> <font color="Maroon" title="c3">y</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon">F<sub>3</sub></font>() )
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>then reconsider </b><font color="Maroon" title="c4">y</font> = <font color="Maroon" title="c3">y</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font> <b>by </b><i><a class="ref" href="funct_2.html#D2" title="FUNCT_2:def.2">FUNCT_2:def 2</a></i>;<br/><b>take </b><font color="Maroon" title="c5">y</font> = <font color="Maroon" title="c4">y</font>;<br/><b>thus </b><a NAME="E5:25_1_1"/>
<font color="Maroon">S<sub>1</sub></font>[<font color="Maroon" title="c2">x</font>,<font color="Maroon" title="c5">y</font>]
 <b>by </b><i><a class="txt" href="bintree1.html#E2:25_1_1"><i><font color="Green" title="E13">A4</font></i></a></i>;<br/></div><b>end;</b></div>
<b>consider </b><font color="Maroon" title="c2">TV</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of  <a href="dtconstr.html#K6" title="DTCONSTR:func.6">Terminals</a> <font color="Maroon">F<sub>1</sub></font>(),<font color="Maroon" title="c1">FAB</font><b> such that </b><br/><a NAME="E4:25_1"/><i><font color="Green" title="E13">A5</font></i>: 
for <font color="Olive" title="b1">e</font> being   <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="dtconstr.html#K6" title="DTCONSTR:func.6">Terminals</a> <font color="Maroon">F<sub>1</sub></font>() holds  <font color="Maroon">S<sub>1</sub></font>[<font color="Olive" title="b1">e</font>,<font color="Maroon" title="c2">TV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">e</font>]
 <b>from </b><i><a class="ref" href="funct_2.html#S3" title="FUNCT_2:sch.3">FUNCT_2:sch 3</a>(<a class="txt" href="bintree1.html#E2:25_1"><i><font color="Green" title="E12">A3</font></i></a>);<br/></i>
<b>defpred </b><font color="Maroon">S<sub>2</sub></font>[   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ,   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ,   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ,   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ] <b>means </b>for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>()<br/> for <font color="Olive" title="b2">ntv</font> being  <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()  st <font color="Olive" title="b2">ntv</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> $4 holds <br/><font color="Olive" title="b2">ntv</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>7</sub></font>($1,$2,$3,<font color="Olive" title="b1">a</font>);<br/>
<div><i><font color="Green" title="E14">A6</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_2"><b>now </b></a><div class="add"><b>let </b><font color="Maroon" title="c3">x</font> be    <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="dtconstr.html#K7" title="DTCONSTR:func.7">NonTerminals</a> <font color="Maroon">F<sub>1</sub></font>();<br/><b>let </b><font color="Maroon" title="c4">y</font>, <font color="Maroon" title="c5">z</font> be    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font>;<br/><b>deffunc </b><font color="Maroon">H<sub>1</sub></font>(   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>()) <b>-&gt; </b>   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>3</sub></font>() = <font color="Maroon">F<sub>7</sub></font>(<font color="Maroon" title="c3">x</font>,<font color="Maroon" title="c4">y</font>,<font color="Maroon" title="c5">z</font>,$1);<br/><b>consider </b><font color="Maroon" title="c6">fab</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()<b> such that </b><br/><a NAME="E2:25_1_2"/><i><font color="Green" title="E15">A7</font></i>: 
for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Maroon" title="c6">fab</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Olive" title="b1">a</font>)
 <b>from </b><i><a class="ref" href="funct_2.html#S4" title="FUNCT_2:sch.4">FUNCT_2:sch 4</a>();<br/></i><a NAME="E3:25_1_2"/>
( <font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c6">fab</font> &amp;  <a href="relset_1.html#K5" title="RELSET_1:func.5">rng</a> <font color="Maroon" title="c6">fab</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon">F<sub>3</sub></font>() )
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>then reconsider </b><font color="Maroon" title="c7">fab</font> = <font color="Maroon" title="c6">fab</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font> <b>by </b><i><a class="ref" href="funct_2.html#D2" title="FUNCT_2:def.2">FUNCT_2:def 2</a></i>;<br/><b>take </b><font color="Maroon" title="c8">fab</font> = <font color="Maroon" title="c7">fab</font>;<br/><b>thus </b><a NAME="E5:25_1_2"/>
<font color="Maroon">S<sub>2</sub></font>[<font color="Maroon" title="c3">x</font>,<font color="Maroon" title="c4">y</font>,<font color="Maroon" title="c5">z</font>,<font color="Maroon" title="c8">fab</font>]
 <b>by </b><i><a class="txt" href="bintree1.html#E2:25_1_2"><i><font color="Green" title="E15">A7</font></i></a></i>;<br/></div><b>end;</b></div>
<b>consider </b><font color="Maroon" title="c3">NTV</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <span class="p1"><a href="zfmisc_1.html#K3" title="ZFMISC_1:func.3">[:</a><span class="default"><span class="p2">(<span class="default"><a href="dtconstr.html#K7" title="DTCONSTR:func.7">NonTerminals</a> <font color="Maroon">F<sub>1</sub></font>()</span>)</span>,<font color="Maroon" title="c1">FAB</font>,<font color="Maroon" title="c1">FAB</font></span><a href="zfmisc_1.html#K3" title="ZFMISC_1:func.3">:]</a></span>,<font color="Maroon" title="c1">FAB</font><b> such that </b><br/><a NAME="E7:25_1"/><i><font color="Green" title="E15">A8</font></i>: 
for <font color="Olive" title="b1">x</font> being   <a href="subset_1.html#M2" title="SUBSET_1:mode.2">Element</a> of  <a href="dtconstr.html#K7" title="DTCONSTR:func.7">NonTerminals</a> <font color="Maroon">F<sub>1</sub></font>()<br/> for <font color="Olive" title="b2">y</font>, <font color="Olive" title="b3">z</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font> holds  <font color="Maroon">S<sub>2</sub></font>[<font color="Olive" title="b1">x</font>,<font color="Olive" title="b2">y</font>,<font color="Olive" title="b3">z</font>,<font color="Maroon" title="c3">NTV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1"><a href="bintree1.html#K3" title="BINTREE1:func.3">[</a><span class="default"><font color="Olive" title="b1">x</font>,<font color="Olive" title="b2">y</font>,<font color="Olive" title="b3">z</font></span><a href="bintree1.html#K3" title="BINTREE1:func.3">]</a></span>]
 <b>from </b><i><a class="ref" href="multop_1.html#S1" title="MULTOP_1:sch.1">MULTOP_1:sch 1</a>(<a class="txt" href="bintree1.html#E5:25_1"><i><font color="Green" title="E14">A6</font></i></a>);<br/></i>
<b>reconsider </b><font color="Maroon" title="c4">f1'</font> = <font color="Maroon">F<sub>4</sub></font>() as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of  <a href="dtconstr.html#K4" title="DTCONSTR:func.4">TS</a> <font color="Maroon">F<sub>1</sub></font>(),<font color="Maroon" title="c1">FAB</font> ;<br/>
<b>reconsider </b><font color="Maroon" title="c5">f2'</font> = <font color="Maroon">F<sub>5</sub></font>() as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of  <a href="dtconstr.html#K4" title="DTCONSTR:func.4">TS</a> <font color="Maroon">F<sub>1</sub></font>(),<font color="Maroon" title="c1">FAB</font> ;<br/>
<b>deffunc </b><font color="Maroon">H<sub>1</sub></font>(  <a href="dtconstr.html#NM2" title="DTCONSTR:NM.2">Terminal</a> of <font color="Maroon">F<sub>1</sub></font>()) <b>-&gt; </b>   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font> = <font color="Maroon" title="c2">TV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> $1;<br/>
<b>deffunc </b><font color="Maroon">H<sub>2</sub></font>(  <a href="dtconstr.html#NM3" title="DTCONSTR:NM.3">NonTerminal</a> of <font color="Maroon">F<sub>1</sub></font>(),   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ,   <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ,   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font>,   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font>) <b>-&gt; </b>   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font> = <font color="Maroon" title="c3">NTV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1"><a href="bintree1.html#K3" title="BINTREE1:func.3">[</a><span class="default">$1,$4,$5</span><a href="bintree1.html#K3" title="BINTREE1:func.3">]</a></span>;<br/>
<div><i><font color="Green" title="E16">A9</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_3"><b>now </b></a><div class="add"><div><b>hereby </b>
<div class="add"><b>let </b><font color="Maroon" title="c6">t</font> be   <a href="dtconstr.html#NM2" title="DTCONSTR:NM.2">Terminal</a> of <font color="Maroon">F<sub>1</sub></font>();<br/><b>consider </b><font color="Maroon" title="c7">g</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()<b> such that </b><br/><a NAME="E2:25_1_3_1"/><i><font color="Green" title="E17">A10</font></i>: 
( <font color="Maroon" title="c7">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>4</sub></font>() <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1">(<span class="default"><a href="dtconstr.html#K8" title="DTCONSTR:func.8">root-tree</a> <font color="Maroon" title="c6">t</font></span>)</span> &amp; ( for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Maroon" title="c7">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>6</sub></font>(<font color="Maroon" title="c6">t</font>,<font color="Olive" title="b1">a</font>) ) )
 <b>by </b><i><a class="txt" href="bintree1.html#E1:25"><i><font color="Green" title="E10">A1</font></i></a></i>;<br/><b>consider </b><font color="Maroon" title="c8">TVt</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><b> such that </b><br/><a NAME="E4:25_1_3_1"/><i><font color="Green" title="E18">A11</font></i>: 
( <font color="Maroon" title="c2">TV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c6">t</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c8">TVt</font> &amp;  <a href="relat_1.html#K1" title="RELAT_1:func.1">dom</a> <font color="Maroon" title="c8">TVt</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>2</sub></font>() &amp;  <a href="relat_1.html#K2" title="RELAT_1:func.2">rng</a> <font color="Maroon" title="c8">TVt</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon">F<sub>3</sub></font>() )
 <b>by </b><i><a class="ref" href="funct_2.html#D2" title="FUNCT_2:def.2">FUNCT_2:def 2</a></i>;<br/><b>reconsider </b><font color="Maroon" title="c9">TVt</font> = <font color="Maroon" title="c8">TVt</font> as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>() <b>by </b><i><a class="txt" href="bintree1.html#E4:25_1_3_1"><i><font color="Green" title="E18">A11</font></i></a>, <a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a>, <a class="ref" href="relset_1.html#T11" title="RELSET_1:th.11">RELSET_1:11</a></i>;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_3_1_1"><b>now </b></a><div class="add"><b>thus </b><a NAME="E1:25_1_3_1_1"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c7">g</font>
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>thus </b><a NAME="E2:25_1_3_1_1"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c9">TVt</font>
 <b>by </b><i><a class="txt" href="bintree1.html#E4:25_1_3_1"><i><font color="Green" title="E18">A11</font></i></a></i>;<br/><b>let </b><font color="Maroon" title="c10">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>assume </b><a NAME="E3:25_1_3_1_1"/>
<font color="Maroon" title="c10">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon">F<sub>2</sub></font>()
 ;<br/><b>then reconsider </b><font color="Maroon" title="c11">xx</font> = <font color="Maroon" title="c10">x</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() ;<br/><font color="Maroon" title="c7">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c11">xx</font> = 
<font color="Maroon">F<sub>6</sub></font>(<font color="Maroon" title="c6">t</font>,<font color="Maroon" title="c11">xx</font>)
<b>by </b><i><a class="txt" href="bintree1.html#E2:25_1_3_1"><i><font color="Green" title="E17">A10</font></i></a></i>
<br/>.= 
<font color="Maroon" title="c9">TVt</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c11">xx</font>
<b>by </b><i><a class="txt" href="bintree1.html#E4:25_1"><i><font color="Green" title="E13">A5</font></i></a>, <a class="txt" href="bintree1.html#E4:25_1_3_1"><i><font color="Green" title="E18">A11</font></i></a></i>
;<br/><b>hence </b><a NAME="E6:25_1_3_1_1"/>
<font color="Maroon" title="c7">g</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c10">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c9">TVt</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c10">x</font>
 ;<br/></div><b>end;</b></div><b>hence </b><a NAME="E7:25_1_3_1"/>
<font color="Maroon" title="c4">f1'</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1">(<span class="default"><a href="dtconstr.html#K8" title="DTCONSTR:func.8">root-tree</a> <font color="Maroon" title="c6">t</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Maroon" title="c6">t</font>)
 <b>by </b><i><a class="txt" href="bintree1.html#E2:25_1_3_1"><i><font color="Green" title="E17">A10</font></i></a>, <a class="txt" href="bintree1.html#E4:25_1_3_1"><i><font color="Green" title="E18">A11</font></i></a>, <a class="ref" href="funct_1.html#T9" title="FUNCT_1:th.9">FUNCT_1:9</a></i>;<br/></div>
<b>end;</b></div><b>let </b><font color="Maroon" title="c6">nt</font> be   <a href="dtconstr.html#NM3" title="DTCONSTR:NM.3">NonTerminal</a> of <font color="Maroon">F<sub>1</sub></font>();<br/><b>let </b><font color="Maroon" title="c7">tl</font>, <font color="Maroon" title="c8">tr</font> be    <a href="dtconstr.html#M1" title="DTCONSTR:mode.1">Element</a> of  <a href="dtconstr.html#K4" title="DTCONSTR:func.4">TS</a> <font color="Maroon">F<sub>1</sub></font>();<br/><b>let </b><font color="Maroon" title="c9">rtl</font>, <font color="Maroon" title="c10">rtr</font> be   <a href="lang1.html#NM1" title="LANG1:NM.1">Symbol</a> of <font color="Maroon">F<sub>1</sub></font>();<br/><b>assume </b><a NAME="E2:25_1_3"/><i><font color="Green" title="E17">A12</font></i>: 
( <font color="Maroon" title="c9">rtl</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="bintree1.html#K1" title="BINTREE1:func.1">root-label</a> <font color="Maroon" title="c7">tl</font> &amp; <font color="Maroon" title="c10">rtr</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="bintree1.html#K1" title="BINTREE1:func.1">root-label</a> <font color="Maroon" title="c8">tr</font> &amp; <font color="Maroon" title="c6">nt</font> <a href="lang1.html#R1" title="LANG1:pred.1">==&gt;</a> <span class="p1"><a href="lang1.html#K4" title="LANG1:func.4">&lt;*</a><span class="default"><font color="Maroon" title="c9">rtl</font>,<font color="Maroon" title="c10">rtr</font></span><a href="lang1.html#K4" title="LANG1:func.4">*&gt;</a></span> )
 ;<br/><b>let </b><font color="Maroon" title="c11">xl</font>, <font color="Maroon" title="c12">xr</font> be    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font>;<br/><b>assume </b><a NAME="E3:25_1_3"/><i><font color="Green" title="E18">A13</font></i>: 
( <font color="Maroon" title="c11">xl</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">f1'</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c7">tl</font> &amp; <font color="Maroon" title="c12">xr</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">f1'</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c8">tr</font> )
 ;<br/><b>consider </b><font color="Maroon" title="c13">g</font>, <font color="Maroon" title="c14">ff1</font>, <font color="Maroon" title="c15">ff2</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()<b> such that </b><br/><a NAME="E5:25_1_3"/><i><font color="Green" title="E19">A14</font></i>: 
( <font color="Maroon" title="c13">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>4</sub></font>() <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c6">nt</font> <a href="trees_4.html#K10" title="TREES_4:func.10">-tree</a> <font color="Maroon" title="c7">tl</font>,<font color="Maroon" title="c8">tr</font></span>)</span> &amp; <font color="Maroon" title="c14">ff1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>4</sub></font>() <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c7">tl</font> &amp; <font color="Maroon" title="c15">ff2</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>4</sub></font>() <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c8">tr</font> &amp; ( for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Maroon" title="c13">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>7</sub></font>(<font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c14">ff1</font>,<font color="Maroon" title="c15">ff2</font>,<font color="Olive" title="b1">a</font>) ) )
 <b>by </b><i><a class="txt" href="bintree1.html#E1:25"><i><font color="Green" title="E10">A1</font></i></a>, <a class="txt" href="bintree1.html#E2:25_1_3"><i><font color="Green" title="E17">A12</font></i></a></i>;<br/><b>consider </b><font color="Maroon" title="c16">ntvnt</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><b> such that </b><br/><a NAME="E7:25_1_3"/><i><font color="Green" title="E20">A15</font></i>: 
( <font color="Maroon" title="c16">ntvnt</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">NTV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1"><a href="bintree1.html#K3" title="BINTREE1:func.3">[</a><span class="default"><font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c11">xl</font>,<font color="Maroon" title="c12">xr</font></span><a href="bintree1.html#K3" title="BINTREE1:func.3">]</a></span> &amp;  <a href="relat_1.html#K1" title="RELAT_1:func.1">dom</a> <font color="Maroon" title="c16">ntvnt</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>2</sub></font>() &amp;  <a href="relat_1.html#K2" title="RELAT_1:func.2">rng</a> <font color="Maroon" title="c16">ntvnt</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon">F<sub>3</sub></font>() )
 <b>by </b><i><a class="ref" href="funct_2.html#D2" title="FUNCT_2:def.2">FUNCT_2:def 2</a></i>;<br/><b>reconsider </b><font color="Maroon" title="c17">ntvnt</font> = <font color="Maroon" title="c16">ntvnt</font> as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>() <b>by </b><i><a class="txt" href="bintree1.html#E7:25_1_3"><i><font color="Green" title="E20">A15</font></i></a>, <a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a>, <a class="ref" href="relset_1.html#T11" title="RELSET_1:th.11">RELSET_1:11</a></i>;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_3_2"><b>now </b></a><div class="add"><b>thus </b><a NAME="E1:25_1_3_2"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c13">g</font>
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>thus </b><a NAME="E2:25_1_3_2"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c17">ntvnt</font>
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>let </b><font color="Maroon" title="c18">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>assume </b><a NAME="E3:25_1_3_2"/>
<font color="Maroon" title="c18">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon">F<sub>2</sub></font>()
 ;<br/><b>then reconsider </b><font color="Maroon" title="c19">xx</font> = <font color="Maroon" title="c18">x</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() ;<br/><font color="Maroon" title="c13">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c19">xx</font> = 
<font color="Maroon">F<sub>7</sub></font>(<font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c11">xl</font>,<font color="Maroon" title="c12">xr</font>,<font color="Maroon" title="c19">xx</font>)
<b>by </b><i><a class="txt" href="bintree1.html#E3:25_1_3"><i><font color="Green" title="E18">A13</font></i></a>, <a class="txt" href="bintree1.html#E5:25_1_3"><i><font color="Green" title="E19">A14</font></i></a></i>
<br/>.= 
<font color="Maroon" title="c17">ntvnt</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c19">xx</font>
<b>by </b><i><a class="txt" href="bintree1.html#E7:25_1"><i><font color="Green" title="E15">A8</font></i></a>, <a class="txt" href="bintree1.html#E7:25_1_3"><i><font color="Green" title="E20">A15</font></i></a></i>
;<br/><b>hence </b><a NAME="E6:25_1_3_2"/>
<font color="Maroon" title="c13">g</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c18">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c17">ntvnt</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c18">x</font>
 ;<br/></div><b>end;</b></div><b>hence </b><a NAME="E10:25_1_3"/>
<font color="Maroon" title="c4">f1'</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c6">nt</font> <a href="trees_4.html#K10" title="TREES_4:func.10">-tree</a> <font color="Maroon" title="c7">tl</font>,<font color="Maroon" title="c8">tr</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>2</sub></font>(<font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c9">rtl</font>,<font color="Maroon" title="c10">rtr</font>,<font color="Maroon" title="c11">xl</font>,<font color="Maroon" title="c12">xr</font>)
 <b>by </b><i><a class="txt" href="bintree1.html#E5:25_1_3"><i><font color="Green" title="E19">A14</font></i></a>, <a class="txt" href="bintree1.html#E7:25_1_3"><i><font color="Green" title="E20">A15</font></i></a>, <a class="ref" href="funct_1.html#T9" title="FUNCT_1:th.9">FUNCT_1:9</a></i>;<br/></div><b>end;</b></div>
<div><i><font color="Green" title="E17">A16</font></i>: <a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_4"><b>now </b></a><div class="add"><div><b>hereby </b>
<div class="add"><b>let </b><font color="Maroon" title="c6">t</font> be   <a href="dtconstr.html#NM2" title="DTCONSTR:NM.2">Terminal</a> of <font color="Maroon">F<sub>1</sub></font>();<br/><b>consider </b><font color="Maroon" title="c7">g</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()<b> such that </b><br/><a NAME="E2:25_1_4_1"/><i><font color="Green" title="E18">A17</font></i>: 
( <font color="Maroon" title="c7">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>5</sub></font>() <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1">(<span class="default"><a href="dtconstr.html#K8" title="DTCONSTR:func.8">root-tree</a> <font color="Maroon" title="c6">t</font></span>)</span> &amp; ( for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Maroon" title="c7">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>6</sub></font>(<font color="Maroon" title="c6">t</font>,<font color="Olive" title="b1">a</font>) ) )
 <b>by </b><i><a class="txt" href="bintree1.html#E2:25"><i><font color="Green" title="E11">A2</font></i></a></i>;<br/><b>consider </b><font color="Maroon" title="c8">TVt</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><b> such that </b><br/><a NAME="E4:25_1_4_1"/><i><font color="Green" title="E19">A18</font></i>: 
( <font color="Maroon" title="c2">TV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c6">t</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c8">TVt</font> &amp;  <a href="relat_1.html#K1" title="RELAT_1:func.1">dom</a> <font color="Maroon" title="c8">TVt</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>2</sub></font>() &amp;  <a href="relat_1.html#K2" title="RELAT_1:func.2">rng</a> <font color="Maroon" title="c8">TVt</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon">F<sub>3</sub></font>() )
 <b>by </b><i><a class="ref" href="funct_2.html#D2" title="FUNCT_2:def.2">FUNCT_2:def 2</a></i>;<br/><b>reconsider </b><font color="Maroon" title="c9">TVt</font> = <font color="Maroon" title="c8">TVt</font> as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>() <b>by </b><i><a class="txt" href="bintree1.html#E4:25_1_4_1"><i><font color="Green" title="E19">A18</font></i></a>, <a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a>, <a class="ref" href="relset_1.html#T11" title="RELSET_1:th.11">RELSET_1:11</a></i>;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_4_1_1"><b>now </b></a><div class="add"><b>thus </b><a NAME="E1:25_1_4_1_1"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c7">g</font>
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>thus </b><a NAME="E2:25_1_4_1_1"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c9">TVt</font>
 <b>by </b><i><a class="txt" href="bintree1.html#E4:25_1_4_1"><i><font color="Green" title="E19">A18</font></i></a></i>;<br/><b>let </b><font color="Maroon" title="c10">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>assume </b><a NAME="E3:25_1_4_1_1"/>
<font color="Maroon" title="c10">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon">F<sub>2</sub></font>()
 ;<br/><b>then reconsider </b><font color="Maroon" title="c11">xx</font> = <font color="Maroon" title="c10">x</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() ;<br/><font color="Maroon" title="c7">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c11">xx</font> = 
<font color="Maroon">F<sub>6</sub></font>(<font color="Maroon" title="c6">t</font>,<font color="Maroon" title="c11">xx</font>)
<b>by </b><i><a class="txt" href="bintree1.html#E2:25_1_4_1"><i><font color="Green" title="E18">A17</font></i></a></i>
<br/>.= 
<font color="Maroon" title="c9">TVt</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c11">xx</font>
<b>by </b><i><a class="txt" href="bintree1.html#E4:25_1"><i><font color="Green" title="E13">A5</font></i></a>, <a class="txt" href="bintree1.html#E4:25_1_4_1"><i><font color="Green" title="E19">A18</font></i></a></i>
;<br/><b>hence </b><a NAME="E6:25_1_4_1_1"/>
<font color="Maroon" title="c7">g</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c10">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c9">TVt</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c10">x</font>
 ;<br/></div><b>end;</b></div><b>hence </b><a NAME="E7:25_1_4_1"/>
<font color="Maroon" title="c5">f2'</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1">(<span class="default"><a href="dtconstr.html#K8" title="DTCONSTR:func.8">root-tree</a> <font color="Maroon" title="c6">t</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>1</sub></font>(<font color="Maroon" title="c6">t</font>)
 <b>by </b><i><a class="txt" href="bintree1.html#E2:25_1_4_1"><i><font color="Green" title="E18">A17</font></i></a>, <a class="txt" href="bintree1.html#E4:25_1_4_1"><i><font color="Green" title="E19">A18</font></i></a>, <a class="ref" href="funct_1.html#T9" title="FUNCT_1:th.9">FUNCT_1:9</a></i>;<br/></div>
<b>end;</b></div><b>let </b><font color="Maroon" title="c6">nt</font> be   <a href="dtconstr.html#NM3" title="DTCONSTR:NM.3">NonTerminal</a> of <font color="Maroon">F<sub>1</sub></font>();<br/><b>let </b><font color="Maroon" title="c7">tl</font>, <font color="Maroon" title="c8">tr</font> be    <a href="dtconstr.html#M1" title="DTCONSTR:mode.1">Element</a> of  <a href="dtconstr.html#K4" title="DTCONSTR:func.4">TS</a> <font color="Maroon">F<sub>1</sub></font>();<br/><b>let </b><font color="Maroon" title="c9">rtl</font>, <font color="Maroon" title="c10">rtr</font> be   <a href="lang1.html#NM1" title="LANG1:NM.1">Symbol</a> of <font color="Maroon">F<sub>1</sub></font>();<br/><b>assume </b><a NAME="E2:25_1_4"/><i><font color="Green" title="E18">A19</font></i>: 
( <font color="Maroon" title="c9">rtl</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="bintree1.html#K1" title="BINTREE1:func.1">root-label</a> <font color="Maroon" title="c7">tl</font> &amp; <font color="Maroon" title="c10">rtr</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="bintree1.html#K1" title="BINTREE1:func.1">root-label</a> <font color="Maroon" title="c8">tr</font> &amp; <font color="Maroon" title="c6">nt</font> <a href="lang1.html#R1" title="LANG1:pred.1">==&gt;</a> <span class="p1"><a href="lang1.html#K4" title="LANG1:func.4">&lt;*</a><span class="default"><font color="Maroon" title="c9">rtl</font>,<font color="Maroon" title="c10">rtr</font></span><a href="lang1.html#K4" title="LANG1:func.4">*&gt;</a></span> )
 ;<br/><b>let </b><font color="Maroon" title="c11">xl</font>, <font color="Maroon" title="c12">xr</font> be    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon" title="c1">FAB</font>;<br/><b>assume </b><a NAME="E3:25_1_4"/><i><font color="Green" title="E19">A20</font></i>: 
( <font color="Maroon" title="c11">xl</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">f2'</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c7">tl</font> &amp; <font color="Maroon" title="c12">xr</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">f2'</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c8">tr</font> )
 ;<br/><b>consider </b><font color="Maroon" title="c13">g</font>, <font color="Maroon" title="c14">ff1</font>, <font color="Maroon" title="c15">ff2</font> being   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>()<b> such that </b><br/><a NAME="E5:25_1_4"/><i><font color="Green" title="E20">A21</font></i>: 
( <font color="Maroon" title="c13">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>5</sub></font>() <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c6">nt</font> <a href="trees_4.html#K10" title="TREES_4:func.10">-tree</a> <font color="Maroon" title="c7">tl</font>,<font color="Maroon" title="c8">tr</font></span>)</span> &amp; <font color="Maroon" title="c14">ff1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>5</sub></font>() <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c7">tl</font> &amp; <font color="Maroon" title="c15">ff2</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>5</sub></font>() <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c8">tr</font> &amp; ( for <font color="Olive" title="b1">a</font> being   <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() holds  <font color="Maroon" title="c13">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Olive" title="b1">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>7</sub></font>(<font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c14">ff1</font>,<font color="Maroon" title="c15">ff2</font>,<font color="Olive" title="b1">a</font>) ) )
 <b>by </b><i><a class="txt" href="bintree1.html#E2:25"><i><font color="Green" title="E11">A2</font></i></a>, <a class="txt" href="bintree1.html#E2:25_1_4"><i><font color="Green" title="E18">A19</font></i></a></i>;<br/><b>consider </b><font color="Maroon" title="c16">ntvnt</font> being   <a href="funct_1.html#NM1" title="FUNCT_1:NM.1">Function</a><b> such that </b><br/><a NAME="E7:25_1_4"/><i><font color="Green" title="E21">A22</font></i>: 
( <font color="Maroon" title="c16">ntvnt</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">NTV</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <span class="p1"><a href="bintree1.html#K3" title="BINTREE1:func.3">[</a><span class="default"><font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c11">xl</font>,<font color="Maroon" title="c12">xr</font></span><a href="bintree1.html#K3" title="BINTREE1:func.3">]</a></span> &amp;  <a href="relat_1.html#K1" title="RELAT_1:func.1">dom</a> <font color="Maroon" title="c16">ntvnt</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>2</sub></font>() &amp;  <a href="relat_1.html#K2" title="RELAT_1:func.2">rng</a> <font color="Maroon" title="c16">ntvnt</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon">F<sub>3</sub></font>() )
 <b>by </b><i><a class="ref" href="funct_2.html#D2" title="FUNCT_2:def.2">FUNCT_2:def 2</a></i>;<br/><b>reconsider </b><font color="Maroon" title="c17">ntvnt</font> = <font color="Maroon" title="c16">ntvnt</font> as   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of <font color="Maroon">F<sub>2</sub></font>(),<font color="Maroon">F<sub>3</sub></font>() <b>by </b><i><a class="txt" href="bintree1.html#E7:25_1_4"><i><font color="Green" title="E21">A22</font></i></a>, <a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a>, <a class="ref" href="relset_1.html#T11" title="RELSET_1:th.11">RELSET_1:11</a></i>;<br/><div><a class="txt" onclick="hs2(this)" href="javascript:()" title="25_1_4_2"><b>now </b></a><div class="add"><b>thus </b><a NAME="E1:25_1_4_2"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c13">g</font>
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>thus </b><a NAME="E2:25_1_4_2"/>
<font color="Maroon">F<sub>2</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="relset_1.html#K4" title="RELSET_1:func.4">dom</a> <font color="Maroon" title="c17">ntvnt</font>
 <b>by </b><i><a class="ref" href="funct_2.html#D1" title="FUNCT_2:def.1">FUNCT_2:def 1</a></i>;<br/><b>let </b><font color="Maroon" title="c18">x</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ;<br/><b>assume </b><a NAME="E3:25_1_4_2"/>
<font color="Maroon" title="c18">x</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon">F<sub>2</sub></font>()
 ;<br/><b>then reconsider </b><font color="Maroon" title="c19">xx</font> = <font color="Maroon" title="c18">x</font> as    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Maroon">F<sub>2</sub></font>() ;<br/><font color="Maroon" title="c13">g</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c19">xx</font> = 
<font color="Maroon">F<sub>7</sub></font>(<font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c11">xl</font>,<font color="Maroon" title="c12">xr</font>,<font color="Maroon" title="c19">xx</font>)
<b>by </b><i><a class="txt" href="bintree1.html#E3:25_1_4"><i><font color="Green" title="E19">A20</font></i></a>, <a class="txt" href="bintree1.html#E5:25_1_4"><i><font color="Green" title="E20">A21</font></i></a></i>
<br/>.= 
<font color="Maroon" title="c17">ntvnt</font> <a href="funct_2.html#K3" title="FUNCT_2:func.3">.</a> <font color="Maroon" title="c19">xx</font>
<b>by </b><i><a class="txt" href="bintree1.html#E7:25_1"><i><font color="Green" title="E15">A8</font></i></a>, <a class="txt" href="bintree1.html#E7:25_1_4"><i><font color="Green" title="E21">A22</font></i></a></i>
;<br/><b>hence </b><a NAME="E6:25_1_4_2"/>
<font color="Maroon" title="c13">g</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c18">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c17">ntvnt</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <font color="Maroon" title="c18">x</font>
 ;<br/></div><b>end;</b></div><b>hence </b><a NAME="E10:25_1_4"/>
<font color="Maroon" title="c5">f2'</font> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <span class="p1">(<span class="default"><font color="Maroon" title="c6">nt</font> <a href="trees_4.html#K10" title="TREES_4:func.10">-tree</a> <font color="Maroon" title="c7">tl</font>,<font color="Maroon" title="c8">tr</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">H<sub>2</sub></font>(<font color="Maroon" title="c6">nt</font>,<font color="Maroon" title="c9">rtl</font>,<font color="Maroon" title="c10">rtr</font>,<font color="Maroon" title="c11">xl</font>,<font color="Maroon" title="c12">xr</font>)
 <b>by </b><i><a class="txt" href="bintree1.html#E5:25_1_4"><i><font color="Green" title="E20">A21</font></i></a>, <a class="txt" href="bintree1.html#E7:25_1_4"><i><font color="Green" title="E21">A22</font></i></a>, <a class="ref" href="funct_1.html#T9" title="FUNCT_1:th.9">FUNCT_1:9</a></i>;<br/></div><b>end;</b></div>
<a NAME="E12:25_1"/>
<font color="Maroon" title="c4">f1'</font> <a href="funct_2.html#R2" title="FUNCT_2:pred.2">=</a> <font color="Maroon" title="c5">f2'</font>
 
<b>from </b><i><a class="ref" href="bintree1.html#S4" target="_self" title="BINTREE1:sch.4">BINTREE1:sch 4</a>(<a class="txt" href="bintree1.html#E10:25_1"><i><font color="Green" title="E16">A9</font></i></a>, <a class="txt" href="bintree1.html#E11:25_1"><i><font color="Green" title="E17">A16</font></i></a>);<br/></i>
<b>hence </b><a NAME="E13:25_1"/>
<font color="Maroon">F<sub>4</sub></font>() <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon">F<sub>5</sub></font>()
 ;<br/>


</div>
