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<div><span class="kw">theorem </span><a NAME="T171"><span class="comment"><font color="firebrick">:: RELAT_1:171</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</font>, <font color="Olive" title="b2">Y</font> being    <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>  holds <br/> (  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  is <font color="Olive" title="b1">X</font> <a href="relat_1.html#V4" title="RELAT_1:attr.4">-defined</a>  &amp;  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  is <font color="Olive" title="b2">Y</font> <a href="relat_1.html#V5" title="RELAT_1:attr.5">-valued</a>  ) <span class="kw">by</span> <span class="lab"><a class="txt" href="relat_1.html#E186"><span class="lab"><font color="Green" title="E63">Lm1</font></span></a></span>;<br/></div></div>
