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<b>let </b><font color="Maroon" title="c1">x0</font>, <font color="Maroon" title="c2">x1</font>, <font color="Maroon" title="c3">x2</font> be   <a href="real_1.html#NM1" title="REAL_1:NM.1">Real</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> for <font color="Olive" title="b1">f</font> being  <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of  <a href="numbers.html#K1" title="NUMBERS:func.1">REAL</a> , <a href="numbers.html#K1" title="NUMBERS:func.1">REAL</a>   st <font color="Olive" title="b1">f</font> is <a href="funct_1.html#V3" title="FUNCT_1:attr.3">constant</a> holds <br/><span class="p1"><a href="diff_1.html#K13" title="DIFF_1:func.13">[!</a><span class="default"><font color="Olive" title="b1">f</font>,<font color="Maroon" title="c1">x0</font>,<font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">x2</font></span><a href="diff_1.html#K13" title="DIFF_1:func.13">!]</a></span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K6" title="NUMBERS:func.6">0</a> </span><br/><b>let </b><font color="Maroon" title="c4">f</font> be   <a href="funct_2.html#NM1" title="FUNCT_2:NM.1">Function</a> of  <a href="numbers.html#K1" title="NUMBERS:func.1">REAL</a> , <a href="numbers.html#K1" title="NUMBERS:func.1">REAL</a> ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> ( <font color="Maroon" title="c4">f</font> is <a href="funct_1.html#V3" title="FUNCT_1:attr.3">constant</a> implies <span class="p1"><a href="diff_1.html#K13" title="DIFF_1:func.13">[!</a><span class="default"><font color="Maroon" title="c4">f</font>,<font color="Maroon" title="c1">x0</font>,<font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">x2</font></span><a href="diff_1.html#K13" title="DIFF_1:func.13">!]</a></span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K6" title="NUMBERS:func.6">0</a>  )</span><br/>







<b>assume </b><a NAME="E1:22"/><i><font color="Green" title="E11">A1</font></i>: 
<font color="Maroon" title="c4">f</font> is <a href="funct_1.html#V3" title="FUNCT_1:attr.3">constant</a>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> <span class="p1"><a href="diff_1.html#K13" title="DIFF_1:func.13">[!</a><span class="default"><font color="Maroon" title="c4">f</font>,<font color="Maroon" title="c1">x0</font>,<font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">x2</font></span><a href="diff_1.html#K13" title="DIFF_1:func.13">!]</a></span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K6" title="NUMBERS:func.6">0</a> </span><br/>

<b>then </b><span class="p1"><a href="diff_1.html#K13" title="DIFF_1:func.13">[!</a><span class="default"><font color="Maroon" title="c4">f</font>,<font color="Maroon" title="c1">x0</font>,<font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">x2</font></span><a href="diff_1.html#K13" title="DIFF_1:func.13">!]</a></span> = 
<span class="p1">(<span class="default"><a href="numbers.html#K6" title="NUMBERS:func.6">0</a>  <a href="real_1.html#K5" title="REAL_1:func.5">-</a> <span class="p2"><a href="diff_1.html#K12" title="DIFF_1:func.12">[!</a><span class="default"><font color="Maroon" title="c4">f</font>,<font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">x2</font></span><a href="diff_1.html#K12" title="DIFF_1:func.12">!]</a></span></span>)</span> <a href="real_1.html#K10" title="REAL_1:func.10">/</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">x0</font> <a href="real_1.html#K9" title="REAL_1:func.9">-</a> <font color="Maroon" title="c3">x2</font></span>)</span>
<b>by </b><i><a class="ref" href="diff_1.html#T30" title="DIFF_1:th.30">DIFF_1:30</a></i>
<br/>.= 
<span class="p1">(<span class="default"><a href="numbers.html#K6" title="NUMBERS:func.6">0</a>  <a href="xcmplx_0.html#K6" title="XCMPLX_0:func.6">-</a> <a href="numbers.html#K6" title="NUMBERS:func.6">0</a> </span>)</span> <a href="real_1.html#K6" title="REAL_1:func.6">/</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">x0</font> <a href="real_1.html#K9" title="REAL_1:func.9">-</a> <font color="Maroon" title="c3">x2</font></span>)</span>
<b>by </b><i><a class="txt" href="#E1:22"><i><font color="Green" title="E11">A1</font></i></a>, <a class="ref" href="diff_1.html#T30" title="DIFF_1:th.30">DIFF_1:30</a></i>
;<br/>
<b>hence </b><a NAME="E3:22"/>
<span class="p1"><a href="diff_1.html#K13" title="DIFF_1:func.13">[!</a><span class="default"><font color="Maroon" title="c4">f</font>,<font color="Maroon" title="c1">x0</font>,<font color="Maroon" title="c2">x1</font>,<font color="Maroon" title="c3">x2</font></span><a href="diff_1.html#K13" title="DIFF_1:func.13">!]</a></span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K6" title="NUMBERS:func.6">0</a> 
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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