SOLUTION: Exact velu of sin22.5?

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Question 905381: Exact velu of sin22.5?
Answer by harpazo(655) About Me  (Show Source):
You can put this solution on YOUR website!
Find the exact value by using half-angle formula.
a)sin22.5=sin(45/2)= sqrt[(1-cos(45))/2]
= sqrt[(1-(sqrt(2)/2))/2]=
Answer: [sqrt[(2-sqrt(2)]]/2