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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E47">Th72</font></span>: <a NAME="T72"><span class="comment"><font color="firebrick">:: CARD_3:72</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</font> being   <a href="funct_1.html#V4" title="FUNCT_1:attr.4">functional</a>   <a href="card_3.html#V2" title="CARD_3:attr.2">with_common_domain</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>   st <font color="Olive" title="b1">X</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1"><a href="tarski.html#K1" title="TARSKI:func.1">{</a><span class="default"><a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a></span><a href="tarski.html#K1" title="TARSKI:func.1">}</a></span> holds <br/> <a href="card_3.html#K9" title="CARD_3:func.9">DOM</a> <font color="Olive" title="b1">X</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a> </div></div>
