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<div><span class="kw">theorem </span><a NAME="T81"><span class="comment"><font color="firebrick">:: SIN_COS:81</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">th</font> being   <a href="xreal_0.html#NM1" title="XREAL_0:NM.1">Real</a>  st <font color="Olive" title="b1">th</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <span class="p1"><a href="rcomp_1.html#K2" title="RCOMP_1:func.2">].</a><span class="default"><a href="numbers.html#K5" title="NUMBERS:func.5">0</a>,<span class="p2">(<span class="default"><a href="sin_cos.html#K28" title="SIN_COS:func.28">PI</a> <a href="xcmplx_0.html#K7" title="XCMPLX_0:func.7">/</a> 2</span>)</span></span><a href="rcomp_1.html#K2" title="RCOMP_1:func.2">.[</a></span> holds <br/> <a href="sin_cos.html#K19" title="SIN_COS:func.19">cos</a> <font color="Olive" title="b1">th</font> <a href="xxreal_0.html#NR4" title="XXREAL_0:NR.4">&gt;</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  <span class="kw">by</span> <span class="lab"><a class="ref" href="sin_cos.html#T80" target="_self" onmouseover="rs('sin_cos/T80')" onmouseout="rh()">Th79</a></span>;<br/></div></div>
