SOLUTION: express in the form a+bi, where a and b are real numbers 8(cos(7pi/4) + isin(7pi/4))

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Question 672290: express in the form a+bi, where a and b are real numbers

8(cos(7pi/4) + isin(7pi/4))
Found 2 solutions by ewatrrr, solver91311:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

8(cos(7pi/4) + isin(7pi/4))= 8%28sqrt%282%29%2F2+-+i%2Asqrt%282%2F2%29%29+=+4sqrt%282%29-+4sqrt%282%29%2Ai

Thought this (cosx,sinx) summary may be useful in Your studies:

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Use the unit circle (or your memory) to find and



Hint: Remember that cosine is the -coordinate and sine is the coordinate on the unit circle.

From and , we get, for this problem:






The rest is just arithmetic.

John

My calculator said it, I believe it, that settles it
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