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<div><span class="kw">theorem </span><a NAME="T21"><span class="comment"><font color="firebrick">:: EUCLID10:21</font></span><br/></a><div class="add">(  <a href="sin_cos6.html#K2" title="SIN_COS6:func.2">arcsin</a> <span class="p1">(<span class="default">1 <a href="xcmplx_0.html#K7" title="XCMPLX_0:func.7">/</a> 2</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> <a href="xcmplx_0.html#K7" title="XCMPLX_0:func.7">/</a> 6 &amp;  <a href="sin_cos6.html#K2" title="SIN_COS6:func.2">arcsin</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="square_1.html#K3" title="SQUARE_1:func.3">sqrt</a> 3</span>)</span> <a href="xcmplx_0.html#K7" title="XCMPLX_0:func.7">/</a> 2</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> <a href="xcmplx_0.html#K7" title="XCMPLX_0:func.7">/</a> 3 )</div></div>
