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Complex number difficulties?

How to solve this and please describe it.

(i^63 + 1/i^101)^4.

3 Answers

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  • Anonymous
    7 years ago
    Favorite Answer

    i^4 = 1, so you can look at the exponents mod 4. Your expression is the same as

    (i^3 + 1/i)^4.

    Now, i^3 = -i and 1/i = -i

    So you have (-i - i)^4

    That's (-2i)^4= (-2)^4 i^4 = 16.

  • ?
    Lv 7
    7 years ago

    i^4 = 1 and so i^60 = (i^4)^15 = 1^15 = 1

    i^63 = i^3 = -i

    Similarly i^104 = 1, and we can write 1/i^101 = i^3/ i^104 = -i

    So now you see that (i^63 + 1/i^101)^4 = (-2i)^4 = 8

    Regards – Ian H

  • Robert
    Lv 7
    7 years ago

    i^63 = -i and i^101 = i, so the expression becomes

    [ (-i + 1) / i ]^4. Now go inside the brackets and

    multiply by i/i:

    [ (1 - i) / -1 ]^4 = (i - 1)^4

    = i^4 - 4i^3 + 6i^2 - 4i + 1

    = 1 + 4i - 6 - 4i + 1

    = -4

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