SOLUTION: State the formula for sin(a+b) and use it to show sin(a+Pi/2)=cos a

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Question 814281: State the formula for sin(a+b) and use it to show sin(a+Pi/2)=cos a
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!
 
Hi,
sin(a + b) = sin a cos b + cos a sin b
= cos a
Note: and
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