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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E13">Th20</font></span>: <a NAME="T22"><span class="comment"><font color="firebrick">:: TOPREAL6:22</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font>, <font color="Olive" title="b2">B</font> being   <a href="subset_1.html#NM2" title="SUBSET_1:NM.2">Subset</a> of <a href="numbers.html#K1" title="NUMBERS:func.1">REAL</a> holds   <a href="card_3.html#K4" title="CARD_3:func.4">product</a> <span class="p1">(<span class="default">(1,2) <a href="funct_4.html#K7" title="FUNCT_4:func.7">--&gt;</a> (<font color="Olive" title="b1">A</font>,<font color="Olive" title="b2">B</font>)</span>)</span> is   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <span class="p1">(<span class="default"><a href="euclid.html#K15" title="EUCLID:func.15">TOP-REAL</a> 2</span>)</span></div></div>
