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<b>let </b><font color="Maroon" title="c1">UA</font> be   <a href="unialg_1.html#NM2" title="UNIALG_1:NM.2">Universal_Algebra</a>;<br/><b>let </b><font color="Maroon" title="c2">f</font>, <font color="Maroon" title="c3">g</font> be   <a href="struct_0.html#NM6" title="STRUCT_0:NM.6">Function</a> of <font color="Maroon" title="c1">UA</font>,<font color="Maroon" title="c1">UA</font>;<br/>





<b>assume </b><a NAME="E1:5"/><i><font color="Green" title="E4">A1</font></i>: 
( <font color="Maroon" title="c2">f</font> is    <a href="fraenkel.html#M2" title="FRAENKEL:mode.2">Element</a> of  <a href="autalg_1.html#K1" title="AUTALG_1:func.1">UAAut</a> <font color="Maroon" title="c1">UA</font> &amp; <font color="Maroon" title="c3">g</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">f</font> <a href="funct_1.html#K2" title="FUNCT_1:func.2">"</a>  )
 ;<br/>

<a NAME="E2:5"/><b>then </b>
<font color="Maroon" title="c2">f</font> <a href="alg_1.html#R4" title="ALG_1:pred.4">is_isomorphism</a> <font color="Maroon" title="c1">UA</font>,<font color="Maroon" title="c1">UA</font>
 
<b>by </b><i><a class="ref" href="autalg_1.html#D1" target="_self" title="AUTALG_1:def.1">Def1</a></i>;<br/>
<b>hence </b><a NAME="E3:5"/>
<font color="Maroon" title="c3">g</font> <a href="alg_1.html#R4" title="ALG_1:pred.4">is_isomorphism</a> <font color="Maroon" title="c1">UA</font>,<font color="Maroon" title="c1">UA</font>
 <b>by </b><i><a class="txt" href="autalg_1.html#E1:5"><i><font color="Green" title="E4">A1</font></i></a>, <a class="ref" href="alg_1.html#T11" title="ALG_1:th.11">ALG_1:11</a></i>;<br/>


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