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<a NAME="E1:3"/><i><font color="Green">E13</font></i>: 
 <a href="arytm_2.html#K2">REAL+</a>  <a href="tarski.html#R1">c=</a> <a href="arytm_2.html#K2">REAL+</a>  <a href="xboole_0.html#K2">\/</a> <span class="p1"><a href="zfmisc_1.html#K2">[:</a><span class="default"><span class="p2"><a href="tarski.html#K1">{</a><span class="default">0</span><a href="tarski.html#K1">}</a></span>,<a href="arytm_2.html#K2">REAL+</a> </span><a href="zfmisc_1.html#K2">:]</a></span>
 
<b>by </b><i><a class="ref" href="xboole_1.html#T7">XBOOLE_1:7</a></i>;<br/>
<a NAME="E2:3"/>
not <span class="p1"><a href="tarski.html#K4">[</a><span class="default">0,0</span><a href="tarski.html#K4">]</a></span> <a href="hidden.html#R2">in</a>  <a href="arytm_2.html#K2">REAL+</a> 
 
<b>by </b><i><a class="ref" href="arytm_2.html#T3">ARYTM_2:3</a></i>;<br/>
<b>hence </b><a NAME="E3:3"/>
 <a href="arytm_2.html#K2">REAL+</a>  <a href="tarski.html#R1">c=</a>  <a href="numbers.html#K1" target="_self">REAL</a> 
 <b>by </b><i>, <a class="ref" href="zfmisc_1.html#T40">ZFMISC_1:40</a></i>;<br/>


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