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#1 2005-10-31 08:07:02

Andorin
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Finding a Cubic Equation from Complex Roots

Hi,

   An exercise is my workbook asks to find a cubic equation with roots of 2, 1+j and 4+2j (where j is the the square root of -1). I am lost as to how to work this out. Any chance of someone guiding me through?

Cheers in advance...

#2 2005-10-31 12:05:56

God
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Re: Finding a Cubic Equation from Complex Roots

Expand:
(x-2)(x-1-i)(x-4-2i)
That should be your answer.

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