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<b>let </b><font color="Maroon">x1</font> be   <a href="struct_0.html#NM1">Element</a> of <a href="complfld.html#K1" target="_self">F_Complex</a> , <font color="Maroon">y1</font> be   <a href="struct_0.html#NM1">Element</a> of <a href="complfld.html#K1" target="_self">F_Complex</a> ;<br/><b>let </b><font color="Maroon">x2</font> be  <a href="xcmplx_0.html#V1">complex</a>  <a href="ordinal1.html#NM1" target="_self">number</a> , <font color="Maroon">y2</font> be  <a href="xcmplx_0.html#V1">complex</a>  <a href="ordinal1.html#NM1" target="_self">number</a> ;<br/>



<b>reconsider </b><font color="Maroon">x3</font> = <font color="Maroon">x2</font>, <font color="Maroon">y3</font> = <font color="Maroon">y2</font> as    <a href="subset_1.html#M1">Element</a> of  <a href="numbers.html#K2">COMPLEX</a>  <b>by </b><i><a class="ref" href="xcmplx_0.html#D2">XCMPLX_0:def 2</a></i>;<br/>
<b>assume </b><a NAME="E2:8"/>
( <font color="Maroon">x1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">x2</font> &amp; <font color="Maroon">y1</font> <a href="hidden.html#R1">=</a> <font color="Maroon">y2</font> )
 ;<br/>

<b>hence </b><font color="Maroon">x1</font> <a href="rlvect_1.html#K4">+</a> <font color="Maroon">y1</font> = 
<a href="binop_2.html#K27">addcomplex</a>  <a href="binop_1.html#K2">.</a> <font color="Maroon">x3</font>,<font color="Maroon">y3</font>
<b>by </b><i/>
<br/>.= 
<font color="Maroon">x2</font> <a href="xcmplx_0.html#K2">+</a> <font color="Maroon">y2</font>
<b>by </b><i><a class="ref" href="binop_2.html#D3">BINOP_2:def 3</a></i>
;<br/><br/>


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