SOLUTION: find value of A when sinA = Sin 2A and A is between 0 and 360 degree

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Question 1148987: find value of A when sinA = Sin 2A and A is between 0 and 360 degree
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


sin%28A%29+=+sin%282A%29

There is only one thing you can do to that to get started: use the identity for sin(2A).

sin%28A%29+=+2sin%28A%29cos%28A%29

Then it's basic algebraic techniques from there: get 0 on one side and factor.

sin%28A%29-2sin%28A%29cos%28A%29+=+0
sin%28A%29%281-2cos%28A%29%29+=+0

sin%28A%29+=+0 or 1-2cos%28A%29+=+0

I'll let you finish from there.