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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E15">th8a</font></span>: <a NAME="T15"><span class="comment"><font color="firebrick">:: PL_AXIOM:15</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">p</font>, <font color="Olive" title="b2">q</font>, <font color="Olive" title="b3">r</font> being   <a href="xboolean.html#V1" title="XBOOLEAN:attr.1">boolean</a>   <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a>  holds  <span class="p1">(<span class="default"><font color="Olive" title="b1">p</font> <a href="xboolean.html#K5" title="XBOOLEAN:func.5">'or'</a> <span class="p2">(<span class="default"><font color="Olive" title="b2">q</font> <a href="xboolean.html#K4" title="XBOOLEAN:func.4">'&amp;'</a> <font color="Olive" title="b3">r</font></span>)</span></span>)</span> <a href="xboolean.html#K7" title="XBOOLEAN:func.7">&lt;=&gt;</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><font color="Olive" title="b1">p</font> <a href="xboolean.html#K5" title="XBOOLEAN:func.5">'or'</a> <font color="Olive" title="b2">q</font></span>)</span> <a href="xboolean.html#K4" title="XBOOLEAN:func.4">'&amp;'</a> <span class="p2">(<span class="default"><font color="Olive" title="b1">p</font> <a href="xboolean.html#K5" title="XBOOLEAN:func.5">'or'</a> <font color="Olive" title="b3">r</font></span>)</span></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="margrel1.html#K7" title="MARGREL1:func.7">TRUE</a> </div></div>
