SOLUTION: Use the double angle identity to find sin(2x) if csc= -square root 19 and cosx>0

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Question 1025242: Use the double angle identity to find sin(2x) if csc= -square root 19 and cosx>0
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Use the double angle identity to find sin(2x) if csc= -square root 19 and cosx>0
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sin = 1/csc = -1/sqrt(19)
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cos = sqrt(1 - sin^2) = sqrt(18)/sqrt(19)
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sin(2x) = 2sin(x)cos(x)
= 2*(-1)*sqrt(18)/19
= -6sqrt(2)/19