SOLUTION: Can someone please help, I have a test tommorow and have no clue what to do on this problem. given sinx=1/4 and 0<x<pi/2, find the exact value of sin2x

Question 78790: Can someone please help, I have a test tommorow and have no clue what to do on this problem.
given sinx=1/4 and 0
Found 2 solutions by mathdoc314, Earlsdon:
Answer by mathdoc314(58) (Show Source): You can put this solution on YOUR website!
This can be solved with a double-angle formula

(I remember it better if I see them both at once)
That x is in the first quadrant is useful to know because there you know that the cosine is positive. Therefore, since , you can solve and find = = .
The double angle formula for tells me exactly.
Answer by Earlsdon(6294) (Show Source): You can put this solution on YOUR website!

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