SOLUTION: use demoivres theorem to find the indicated power of the complex number [2√2(cos(3π/7)+isin(3π/7)]^−4

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Question 970867: use demoivres theorem to find the indicated power of the complex number
[2√2(cos(3π/7)+isin(3π/7)]^−4
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
use demoivres theorem to find the indicated power of the complex number
[2√2(cos(3π/7)+isin(3π/7)]^−4
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!st: Find the 4th power of 2sqrt(2)cis(3pi/7)
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r = (2sqrt(2))^4 = (2^(3/2))^4 = 2*6 = 64
theta = (3/7)pi
n = 4
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Ans: 64cis(12pi/7)
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2nd: Find the inverse
(1/64)cis(-12pi/7)
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Cheers,
Stan H.
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