SOLUTION: Sin(Theta) = p Find cos (Theta) Where domain is Pi/2 to Pi

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Question 1093680: Sin(Theta) = p
Find cos (Theta)
Where domain is Pi/2 to Pi
Found 2 solutions by CubeyThePenguin, ikleyn:
Answer by CubeyThePenguin(3113) About Me  (Show Source):
You can put this solution on YOUR website!
sin(x) = p

cos(x) = sqrt%281+-+p%5E2%29

Answer by ikleyn(52879) About Me  (Show Source):
You can put this solution on YOUR website!
.

The solution and the answer by @CubeyThePenguin both are incorrect. 


cos(theta) = +/- sqrt%281-sin%5E2%28theta%29%29 = +/- sqrt%281-p%5E2%29.


In the domain  from  pi%2F2  to  pi,  cosine is negative, so we use the  " - "  sign in the formula


    cos(theta) = - sqrt%281-p%5E2%29.