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Math Help - dividing complex numbers

  1. #1
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    dividing complex numbers

    Hello, I am trying to divide:

    (12-16i) / (1.414+1.414i)

    As I understand, a method to do this is to multiply the first set by the conjugate of the second eg.
    (12-16i) * (1.414 - 1.414i)

    If I do that, and then calculate out I get:

    16.97-16.97i-22.62i+22.62i^2 / 2-2i+2i-2i^2
    simplified to:
    16.97-39.59i+22.62i^2 / 2-2i^2
    simplified to:
    39.59-39.59i / 2-2
    simplified to:
    39.59-39.59i

    However, I know the answer should be -1.414 - 9.901i
    Can someone see where I am going wrong ?
    Thanks kindly for any help.
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  2. #2
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    It's because the denominator is 2 - 2i^2 = 2 - (-2) = 2 + 2 = 4.
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  3. #3
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