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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E16">Th12</font></span>: <a NAME="T12"><span class="comment"><font color="firebrick">:: CLASSES5:12</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">U</font> being   <a href="classes2.html#NM1" title="CLASSES2:NM.1">Universe</a><br/>  for <font color="Olive" title="b2">x</font> being    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Olive" title="b1">U</font><br/>  for <font color="Olive" title="b3">x1</font>, <font color="Olive" title="b4">x2</font>, <font color="Olive" title="b5">x3</font>, <font color="Olive" title="b6">x4</font> being    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>   st <font color="Olive" title="b2">x</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="xtuple_0.html#K6" title="XTUPLE_0:func.6">[</a><span class="default"><font color="Olive" title="b3">x1</font>,<font color="Olive" title="b4">x2</font>,<font color="Olive" title="b5">x3</font>,<font color="Olive" title="b6">x4</font></span><a href="xtuple_0.html#K6" title="XTUPLE_0:func.6">]</a></span> holds <br/>( <font color="Olive" title="b3">x1</font> is    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Olive" title="b1">U</font> &amp; <font color="Olive" title="b4">x2</font> is    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Olive" title="b1">U</font> &amp; <font color="Olive" title="b5">x3</font> is    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Olive" title="b1">U</font> &amp; <font color="Olive" title="b6">x4</font> is    <a href="subset_1.html#M1" title="SUBSET_1:mode.1">Element</a> of <font color="Olive" title="b1">U</font> )</div></div>
