SOLUTION: please help prove: [sin(y/2)+cos(y/2)]^2^=1+siny

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Question 234312: please help prove: [sin(y/2)+cos(y/2)]^2^=1+siny
Answer by Edwin McCravy(20060)   (Show Source): You can put this solution on YOUR website!



Square the left side:



Swap the last two terms on the left side:




Use the identity  to replace
the first two terms by 1.



Use the identity  to replace
the second term on the left by  







Edwin
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