SOLUTION: Help!!! I don't know how to do this? sin(2sin^-1(5/13))

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Question 939561: Help!!! I don't know how to do this?
sin(2sin^-1(5/13))
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
sin(2sin^-1(5/13))
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That is a double-angle statement.
The angle is sin^-1(5/13) = x
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sin(2x) = 2sin(x)cos(x)
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sin[sin^-1(5/13)] = 5/13
cos(sin^-1(5/13)] = sqrt(13^2-5^2)/13 = sqrt(144)/13 = 12/13
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Ans: 2(5/13)(12/13) = 120/169 = 0.71
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Cheers,
Stan H.
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