SOLUTION: Use a half-angle formula to find the exact value of sin ((3pi)/8) Thanks!!

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Question 682705: Use a half-angle formula to find the exact value of sin ((3pi)/8)

Thanks!!
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Use a half-angle formula to find the exact value of sin ((3pi)/8)
Identity:sin(s/2)=±√[(1-cos s)/2]
sin(3π/8)=sin[(3π/4)/2]=√[1-cos(3π/4)/2]=√[1-(-√2/2)/2]=√[(1+√2/2)/2]
sin(3π/8)=√[(1+√2/2)/2]
check with calculator:
sin(3π/8)≈.9238..
√[(1+√2/2)/2]≈.9238..