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**Andorin****Member**- Registered: 2005-10-24
- Posts: 4

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...

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**God****Member**- Registered: 2005-08-25
- Posts: 59

Expand:

(x-2)(x-1-i)(x-4-2i)

That should be your answer.

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