SOLUTION: (cosx - isinx)^5

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Question 1084358: (cosx - isinx)^5
Answer by math_helper(2461) About Me  (Show Source):
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+a+%2B+b%2Ai++=+r%2Acos%28theta%29+%2B+i%2Ar%2Asin%28theta%29+=++r%2Ae%5E%28i%2Atheta%29+
where
+r+=+sqrt%28a%5E2%2Bb%5E2%29+ and +theta+=+tan%28-1%29%28b%2Fa%29+
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and +theta+=+tan%5E-1%28-sin%28x%29+%2F+cos%28x%29%29+=+tan%5E-1%28-tan%28x%29%29+=+-x+
so:
Using +cos%28-theta%29+=+cos%28theta%29+ and +sin%28-theta%29+=+-sin%28theta%29+ for +0%3C=theta%3C=pi+
lets us simplify to:
+highlight%28cos%285x%29+-+i%2Asin%285x%29%29+