<?xml version="1.0"?>
<div><span class="kw">theorem </span><a NAME="T93"><span class="comment"><font color="firebrick">:: SIN_COS6:93</font></span><br/></a><div class="add"> <a href="sin_cos6.html#K4" title="SIN_COS6:func.4">arccos</a> <span class="p1">(<span class="default"><a href="xcmplx_0.html#K4" title="XCMPLX_0:func.4">-</a> 1</span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="sin_cos.html#K28" title="SIN_COS:func.28">PI</a>  <span class="kw">by</span> <span class="lab"><a class="ref" href="sin_cos6.html#T92" target="_self" onmouseover="rs('sin_cos6/T92')" onmouseout="rh()">Th92</a>, <a class="ref" href="sin_cos.html#T77" onmouseover="rs('sin_cos/T77')" onmouseout="rh()">SIN_COS:77</a></span>;<br/></div></div>
