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<div><span class="kw">theorem </span><a NAME="T56"><span class="comment"><font color="firebrick">:: QUATERNI:56</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">z1</font>, <font color="Olive" title="b2">z2</font> being   <a href="quaterni.html#NM1" title="QUATERNI:NM.1">Quaternion</a> holds  <span class="p1">(<span class="default"><font color="Olive" title="b1">z1</font> <a href="quaterni.html#K24" title="QUATERNI:func.24">-</a> <font color="Olive" title="b2">z2</font></span>)</span> <a href="quaterni.html#K26" title="QUATERNI:func.26">*'</a>  <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <span class="p1">(<span class="default"><font color="Olive" title="b1">z1</font> <a href="quaterni.html#K26" title="QUATERNI:func.26">*'</a></span>)</span> <a href="quaterni.html#K24" title="QUATERNI:func.24">-</a> <span class="p1">(<span class="default"><font color="Olive" title="b2">z2</font> <a href="quaterni.html#K26" title="QUATERNI:func.26">*'</a></span>)</span></div></div>
