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<b>let </b><font color="Maroon" title="c1">F</font> be    <a href="supinf_1.html#M3" title="SUPINF_1:mode.3">bool_DOMAIN</a> of  <a href="numbers.html#K6" title="NUMBERS:func.6">ExtREAL</a> ;<br/><b>let </b><font color="Maroon" title="c2">S</font> be  non <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a> <a href="subset_1.html#NM2" title="SUBSET_1:NM.2">Subset</a> of <a href="numbers.html#K6" title="NUMBERS:func.6">ExtREAL</a> ;<br/>



<b>assume </b><a NAME="E1:91"/><i><font color="Green" title="E60">A1</font></i>: 
<font color="Maroon" title="c2">S</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="tarski.html#K3" title="TARSKI:func.3">union</a> <font color="Maroon" title="c1">F</font>
 ;<br/>

<b>set </b><font color="Maroon" title="c3">a</font> =  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <font color="Maroon" title="c2">S</font>;<br/>
<b>set </b><font color="Maroon" title="c4">b</font> =  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <span class="p1">(<span class="default"><a href="supinf_1.html#K9" title="SUPINF_1:func.9">INF</a> <font color="Maroon" title="c1">F</font></span>)</span>;<br/>
<a NAME="E2:91"/><i><font color="Green" title="E61">A2</font></i>: 
 <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <span class="p1">(<span class="default"><a href="supinf_1.html#K9" title="SUPINF_1:func.9">INF</a> <font color="Maroon" title="c1">F</font></span>)</span> is    <a href="supinf_1.html#M2" title="SUPINF_1:mode.2">minorant</a> of <font color="Maroon" title="c2">S</font>
 
<b>by </b><i><a class="txt" href="supinf_1.html#E1:91"><i><font color="Green" title="E60">A1</font></i></a>, <a class="ref" href="supinf_1.html#T118" target="_self" title="SUPINF_1:th.118">Th118</a></i>;<br/>
<a NAME="E3:91"/>
 <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <font color="Maroon" title="c2">S</font> is    <a href="supinf_1.html#M2" title="SUPINF_1:mode.2">minorant</a> of  <a href="supinf_1.html#K9" title="SUPINF_1:func.9">INF</a> <font color="Maroon" title="c1">F</font>
 
<b>by </b><i><a class="txt" href="supinf_1.html#E1:91"><i><font color="Green" title="E60">A1</font></i></a>, <a class="ref" href="supinf_1.html#T117" target="_self" title="SUPINF_1:th.117">Th117</a></i>;<br/>
<a NAME="E4:91"/><b>then </b>
(  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <font color="Maroon" title="c2">S</font> <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a>  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <span class="p1">(<span class="default"><a href="supinf_1.html#K9" title="SUPINF_1:func.9">INF</a> <font color="Maroon" title="c1">F</font></span>)</span> &amp;  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <span class="p1">(<span class="default"><a href="supinf_1.html#K9" title="SUPINF_1:func.9">INF</a> <font color="Maroon" title="c1">F</font></span>)</span> <a href="xxreal_0.html#R1" title="XXREAL_0:pred.1">&lt;=</a>  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <font color="Maroon" title="c2">S</font> )
 
<b>by </b><i><a class="txt" href="supinf_1.html#E2:91"><i><font color="Green" title="E61">A2</font></i></a>, <a class="ref" href="supinf_1.html#D17" target="_self" title="SUPINF_1:def.17">Def17</a></i>;<br/>
<b>hence </b><a NAME="E5:91"/>
 <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <font color="Maroon" title="c2">S</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="supinf_1.html#K7" title="SUPINF_1:func.7">inf</a> <span class="p1">(<span class="default"><a href="supinf_1.html#K9" title="SUPINF_1:func.9">INF</a> <font color="Maroon" title="c1">F</font></span>)</span>
 <b>by </b><i><a class="txt" href="supinf_1.html#E26"><i><font color="Green" title="E6">Lm3</font></i></a></i>;<br/>


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