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<span class="kw">set </span><font color="Maroon" title="c2">z</font> = <span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span>;<br/>
<span class="kw">set </span><font color="Maroon" title="c3">p1</font> = <span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K4" title="RATFUNC1:func.4">`1</a> ;<br/>
<span class="kw">set </span><font color="Maroon" title="c4">p2</font> = <span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K5" title="RATFUNC1:func.5">`2</a> ;<br/>
<div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="65_1_1_1"><span class="kw">now </span> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  not <span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K4" title="RATFUNC1:func.4">`1</a> ,<span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K5" title="RATFUNC1:func.5">`2</a>  <a href="ratfunc1.html#R2" title="RATFUNC1:pred.2">have_a_common_root</a> </span></a><div class="add"><span class="kw">assume </span><a NAME="E1:65_1_1_1"/>
<span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K4" title="RATFUNC1:func.4">`1</a> ,<span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K5" title="RATFUNC1:func.5">`2</a>  <a href="ratfunc1.html#R2" title="RATFUNC1:pred.2">have_a_common_root</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> contradiction</span><br/><span class="kw">then </span><span class="kw">consider </span><font color="Maroon" title="c5">x</font> being   <a href="struct_0.html#NM1" title="STRUCT_0:NM.1">Element</a> of <font color="Maroon" title="c1">L</font><span class="kw"> such that </span><br/><a NAME="E3:65_1_1_1"/><span class="lab"><font color="Green" title="E19">A1</font></span>: 
<font color="Maroon" title="c5">x</font> <a href="ratfunc1.html#R1" title="RATFUNC1:pred.1">is_a_common_root_of</a> <span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K4" title="RATFUNC1:func.4">`1</a> ,<span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K5" title="RATFUNC1:func.5">`2</a> 
 ;<br/><a NAME="E4:65_1_1_1"/>
<font color="Maroon" title="c5">x</font> <a href="polynom5.html#R1" title="POLYNOM5:pred.1">is_a_root_of</a> <span class="p1"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p2">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K5" title="RATFUNC1:func.5">`2</a> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:65_1_1_1"><span class="lab"><font color="Green" title="E19">A1</font></span></a></span>;<br/><a NAME="E5:65_1_1_1"/><span class="kw">then </span>
 <a href="polynom4.html#K2" title="POLYNOM4:func.2">eval</a> (<span class="p1">(<span class="default"><span class="p2"><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">[</a><span class="default"><span class="p3">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span>,<span class="p3">(<span class="default"><a href="polynom3.html#K10" title="POLYNOM3:func.10">1_.</a> <font color="Maroon" title="c1">L</font></span>)</span></span><a href="ratfunc1.html#K3" title="RATFUNC1:func.3">]</a></span> <a href="ratfunc1.html#K5" title="RATFUNC1:func.5">`2</a></span>)</span>,<font color="Maroon" title="c5">x</font>) <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="struct_0.html#K4" title="STRUCT_0:func.4">0.</a> <font color="Maroon" title="c1">L</font>
 <span class="kw">by</span> <span class="lab"><a class="ref" href="polynom5.html#D7" onmouseover="rs('polynom5/D7')" onmouseout="rh()">POLYNOM5:def 7</a></span>;<br/><span class="kw">hence </span><a NAME="E6:65_1_1_1"/>
contradiction
 <span class="kw">by</span> <span class="lab"><a class="ref" href="polynom4.html#T18" onmouseover="rs('polynom4/T18')" onmouseout="rh()">POLYNOM4:18</a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/></div><span class="kw">end;</span></div>
<span class="kw">hence </span><a NAME="E2:65_1_1"/>
 <a href="ratfunc1.html#K8" title="RATFUNC1:func.8">1._</a> <font color="Maroon" title="c1">L</font> is  <a href="ratfunc1.html#V4" title="RATFUNC1:attr.4">irreducible</a> 
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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