SOLUTION: find the exact value for sin(Θ/2) given sin Θ=12/13; Θ is obtuse.

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Question 916840: find the exact value for sin(Θ/2) given sin Θ=12/13; Θ is obtuse.
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!










But since is obtuse is in the second quadrant where cosine is negative,



Since



We have



Rationalizing the denominator



But since is in quadrant 2, must be in quadrant 1 (). And since the sine is positive in quadrant 1:



John

My calculator said it, I believe it, that settles it