SOLUTION: Prove (SinA+CosA)^2=1+Sin2A Thank you

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Question 400653: Prove (SinA+CosA)^2=1+Sin2A
Thank you
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Expanding the left side, we get

sin%5E2%28a%29+%2B+2sin%28a%29cos%28a%29+%2B+cos%5E2%28a%29 Since sin%5E2%28a%29+%2B+cos%5E2%28a%29+=+1, and 2sin%28a%29cos%28a%29+=+sin%282a%29, the expression is equivalent to

1+%2B+sin%282a%29, and we're done.