
<A NAME=find_companion>

<TITLE>find_companion</TITLE></A>
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<B>FIND_COMPANION</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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syntax: </H3>
<em>find_companion</em>(&lt;matrix&gt;,&lt;x&gt;) 
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&lt;matrix&gt; :- a 
<A HREF=r37_0345.html>matrix</A>. 
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&lt;x&gt; :- the variable. 
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Given a companion matrix, <em>find_companion</em> finds the polynomial 
from which it was made. 
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examples: </H3>
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C := companion(x^4+17*x^3-9*x^2+11,x); 


       [0  0  0  -11]
       [            ]
       [1  0  0   0 ]
  c := [            ]
       [0  1  0   9 ]
       [            ]
       [0  0  1  -17]



find_companion(C,x); 

   4     3    2
  x +17*x -9*x +11

</TT></PRE><P>Related functions: 

<A HREF=r37_0584.html>companion</A>. 
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