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<b>let </b><font color="Maroon">S1</font> be  non <a href="struct_0.html#V3">empty</a> <a href="pre_topc.html#NM1">TopSpace</a>, <font color="Maroon">S2</font> be  non <a href="struct_0.html#V3">empty</a> <a href="pre_topc.html#NM1">TopSpace</a>, <font color="Maroon">T1</font> be  non <a href="struct_0.html#V3">empty</a> <a href="pre_topc.html#NM1">TopSpace</a>, <font color="Maroon">T2</font> be  non <a href="struct_0.html#V3">empty</a> <a href="pre_topc.html#NM1">TopSpace</a>;<br/><b>let </b><font color="Maroon">f</font> be  <a href="pre_topc.html#V5">continuous</a> <a href="struct_0.html#NM6">Function</a> of <font color="Maroon">S1</font>,<font color="Maroon">T1</font>;<br/><b>let </b><font color="Maroon">g</font> be  <a href="pre_topc.html#V5">continuous</a> <a href="struct_0.html#NM6">Function</a> of <font color="Maroon">S2</font>,<font color="Maroon">T2</font>;<br/>





<a NAME="E1:35"/>
for <font color="Olive">P1</font> being  <a href="struct_0.html#NM2">Subset</a> of <span class="p1"><a href="borsuk_1.html#K5">[:</a><span class="default"><font color="Maroon">T1</font>,<font color="Maroon">T2</font></span><a href="borsuk_1.html#K5">:]</a></span>  st <font color="Olive">P1</font> is <a href="pre_topc.html#V3">open</a> holds <br/><span class="p1"><a href="borsuk_2.html#K3" target="_self">[:</a><span class="default"><font color="Maroon">f</font>,<font color="Maroon">g</font></span><a href="borsuk_2.html#K3" target="_self">:]</a></span> <a href="relset_1.html#K11">"</a> <font color="Olive">P1</font> is <a href="pre_topc.html#V3">open</a>
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E2:35"/>
<span class="p1"><a href="borsuk_2.html#K3" target="_self">[:</a><span class="default"><font color="Maroon">f</font>,<font color="Maroon">g</font></span><a href="borsuk_2.html#K3" target="_self">:]</a></span> is <a href="pre_topc.html#V5">continuous</a>
 <b>by </b><i><a class="ref" href="tops_2.html#T55">TOPS_2:55</a></i>;<br/>


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