document.write( "Question 1099340: Can someone please help me with this question - Thanks
\n" ); document.write( "Let P(z)= \"+z%5E3-kz%5E2%2B22z-20+\" , k is a rational number.
\n" ); document.write( "3+i is a root of the equation P(z)=0
\n" ); document.write( "Find value of k.
\n" ); document.write( "Find the other root of the equation P(z)=0\r
\n" ); document.write( "\n" ); document.write( "I got two roots and multiplied them together and got \"+z%5E2-6z%2B10+\", I did this by z=3+i and z=3-i, (z-3-i)(z-3+i).
\n" ); document.write( "I originally thought I had to divide \"+z%5E3-kz%5E2%2B22z-20+\" by \"+z%5E2-6z%2B10+\" but I don't think I can divide with the k in the way.
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Algebra.Com's Answer #713790 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
\"P%28z%29=%28z%5E2-6z%2B10%29%28z-r%29\" where \"r\" is the other root.
\n" ); document.write( "The independent term is \"-10r=-20\" ,
\n" ); document.write( "so \"r=2\" or we were deceived about \"3%2Bi\" being a root.
\n" ); document.write( "Let's multiply.
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\n" ); document.write( "If that polynomial is the same function as \"P%28z%29=z%5E3-kz%5E2%2B22z-20+\"
\n" ); document.write( "(same values for every complex value of \"z\" ),
\n" ); document.write( "then \"k=8\" .
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