<?xml version="1.0"?>
<div class="add">

<b>let </b><font color="Maroon">c<sub>4</sub></font>, <font color="Maroon">c<sub>5</sub></font> be   <a href="incsp_1.html#NM3">PLANE</a> of <font color="Maroon">c<sub>1</sub></font>;<br/>



<b>assume </b><a NAME="E1:49_1_1"/><i><font color="Green">E36</font></i>: 
( <font color="Maroon">c<sub>2</sub></font> <a href="incsp_1.html#R3" target="_self">on</a> <font color="Maroon">c<sub>4</sub></font> &amp; <font color="Maroon">c<sub>3</sub></font> <a href="incsp_1.html#R3" target="_self">on</a> <font color="Maroon">c<sub>4</sub></font> &amp; <font color="Maroon">c<sub>2</sub></font> <a href="incsp_1.html#R3" target="_self">on</a> <font color="Maroon">c<sub>5</sub></font> &amp; <font color="Maroon">c<sub>3</sub></font> <a href="incsp_1.html#R3" target="_self">on</a> <font color="Maroon">c<sub>5</sub></font> )
 ;<br/>

<b>consider </b><font color="Maroon">c<sub>6</sub></font> being   <a href="incsp_1.html#NM3">PLANE</a> of <font color="Maroon">c<sub>1</sub></font><b> such that </b><br/><a NAME="E3:49_1_1"/><i><font color="Green">E37</font></i>: 
for <font color="Olive">b<sub>1</sub></font> being  <a href="incsp_1.html#NM3">PLANE</a> of <font color="Maroon">c<sub>1</sub></font> holds <br/>( ( <font color="Maroon">c<sub>2</sub></font> <a href="incsp_1.html#R3" target="_self">on</a> <font color="Olive">b<sub>1</sub></font> &amp; <font color="Maroon">c<sub>3</sub></font> <a href="incsp_1.html#R3" target="_self">on</a> <font color="Olive">b<sub>1</sub></font> ) iff <font color="Maroon">c<sub>6</sub></font> <a href="hidden.html#R1">=</a> <font color="Olive">b<sub>1</sub></font> )
 <b>by </b><i><a class="txt" href="incsp_1.html#E1:49"><i><font color="Green">E34</font></i></a>, <a class="txt" href="incsp_1.html#E2:49"><i><font color="Green">E35</font></i></a>, <a class="ref" href="incsp_1.html#T49" target="_self">Th49</a></i>;<br/>
<a NAME="E4:49_1_1"/>
( <font color="Maroon">c<sub>4</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>6</sub></font> &amp; <font color="Maroon">c<sub>5</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>6</sub></font> )
 
<b>by </b><i><a class="txt" href="incsp_1.html#E1:49_1_1"><i><font color="Green">E36</font></i></a>, <a class="txt" href="incsp_1.html#E3:49_1_1"><i><font color="Green">E37</font></i></a></i>;<br/>
<b>hence </b><a NAME="E5:49_1_1"/>
<font color="Maroon">c<sub>4</sub></font> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>5</sub></font>
 ;<br/>


</div>
