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Math Help - Finding roots of complex numbers

  1. #1
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    Finding roots of complex numbers

    The question:

    i) Find the complex square roots of -24-10i by solving (x+iy)^2 = -24-10i for x, y real.

    ii) Hence, find the roots of the quadratic z^2-(1+i)z + (6+3i) in "a+ib" form where a, b are real numbers.

    My attempt:
    i) I got the answer \pm(1-5i)
    ii) This is where I have trouble. The question appears to suggest that I use the result of part i) to solve part ii). I'm not sure how they relate. I was thinking of using the quadratic formula, but perhaps there's a quicker way?

    Any assistance would be greatly appreciated!
    Last edited by Glitch; August 25th 2010 at 03:05 AM.
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  2. #2
    Pim
    Pim is offline
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    I think, unless you can factor the quadratic by heart, the quadratic formula is the best way to go.
    This relates to i) as follows: In the quadratic formula, you will need to calculate the roots of the discriminant. You learned this in i)
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  3. #3
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    Ahh, I see. Thank you!
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