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<b>let </b><font color="Maroon" title="c1">K</font> be   <a href="vectsp_1.html#NM3" title="VECTSP_1:NM.3">Field</a>;<br/><b>let </b><font color="Maroon" title="c2">n</font> be   <a href="nat_1.html#NM1" title="NAT_1:NM.1">Nat</a>;<br/><b>let </b><font color="Maroon" title="c3">M1</font> be   <a href="matrix_1.html#NM5" title="MATRIX_1:NM.5">Matrix</a> of <font color="Maroon" title="c2">n</font>,<font color="Maroon" title="c1">K</font>;<br/>





<b>assume </b><a NAME="E1:36"/><i><font color="Green" title="E17">A1</font></i>: 
<font color="Maroon" title="c3">M1</font> is <a href="matrix_6.html#V2" title="MATRIX_6:attr.2">symmetric</a>
 ;<br/>

<span class="p1">(<span class="default"><a href="matrix_6.html#K1" title="MATRIX_6:func.1">-</a> <font color="Maroon" title="c3">M1</font></span>)</span> <a href="matrix_1.html#K5" title="MATRIX_1:func.5">@</a>  = 
 <a href="matrix_6.html#K1" title="MATRIX_6:func.1">-</a> <span class="p1">(<span class="default"><font color="Maroon" title="c3">M1</font> <a href="matrix_1.html#K5" title="MATRIX_1:func.5">@</a> </span>)</span>
<b>by </b><i><a class="ref" href="matrix_6.html#T27" target="_self" title="MATRIX_6:th.27">Th27</a></i>
<br/>.= 
 <a href="matrix_6.html#K1" title="MATRIX_6:func.1">-</a> <font color="Maroon" title="c3">M1</font>
<b>by </b><i><a class="txt" href="matrix_6.html#E1:36"><i><font color="Green" title="E17">A1</font></i></a>, <a class="ref" href="matrix_6.html#D5" target="_self" title="MATRIX_6:def.5">Def5</a></i>
;<br/>
<b>hence </b><a NAME="E3:36"/>
 <a href="matrix_6.html#K1" title="MATRIX_6:func.1">-</a> <font color="Maroon" title="c3">M1</font> is <a href="matrix_6.html#V2" title="MATRIX_6:attr.2">symmetric</a>
 <b>by </b><i><a class="ref" href="matrix_6.html#D5" target="_self" title="MATRIX_6:def.5">Def5</a></i>;<br/>


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