SOLUTION: Compound angle identities Find the exact value of tan 15 show answer in radians for example (1+sqrt(3))/2 Thank you in advance

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Question 1047792: Compound angle identities
Find the exact value of tan 15
show answer in radians for example (1+sqrt(3))/2
Thank you in advance

Found 2 solutions by Alan3354, advanced_Learner:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the exact value of tan 15
show answer in radians for example (1+sqrt(3))/2
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The tangent is not in radians.
The angle might be in radians, but I suspect you mean tan(15) degs.
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tan%28x%2F2%29+=+sin%28x%29%2F%281+%2B+cos%28x%29%29
tan%2815%29+=+tan%2830%2F2%29+=+sin%2830%29%2F%281+%2B+cos%2830%29%29
tan%2815%29+=+2+-+sqrt%283%29


Answer by advanced_Learner(501) About Me  (Show Source):
You can put this solution on YOUR website!
tan15=%28sin15%29%2F%28cos15%29
can you go from there to show that
tan15=%28sin45-sin30%29%2F%28cos45-cos30%29
and finaly
tan15=%28sqrt%282%29%2Bsqrt%283%29-sqrt%286%29-2%29