SOLUTION: How do you find the power in rectangular and trigonometric form when given {{{ (-1+i)^7 }}}?

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Question 1116773: How do you find the power in rectangular and trigonometric form when given +%28-1%2Bi%29%5E7+?
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


Put the expression in r%2Acis%28x%29 form and use deMoivre's Theorem.

-1%2Bi+=+sqrt%282%29%2Acis%283pi%2F4%29

deMoivre's Theorem says you raise that number to a power by raising the modulus to the power and multiplying the angle by the power. So



Then convert back to rectangular form; a modulus of 8*sqrt(2) and an angle of 5pi/4 gives the rectangular form as -8-8i.