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<div><span class="kw">theorem </span><a NAME="T43"><span class="comment"><font color="firebrick">:: SIN_COS9:43</font></span><br/></a><div class="add">(  <a href="sin_cos9.html#K3" title="SIN_COS9:func.3">arctan</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  &amp; <a href="sin_cos9.html#K1" title="SIN_COS9:func.1">arctan</a> <a href="funct_1.html#K1" title="FUNCT_1:func.1">.</a> <a href="numbers.html#K5" title="NUMBERS:func.5">0</a> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="numbers.html#K5" title="NUMBERS:func.5">0</a>  )</div></div>
