SOLUTION: find the exact value of sin 20 if son0= 4/5 andquadrant I 0 is in quadrant 1

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Question 1078612: find the exact value of sin 20 if son0= 4/5 andquadrant I 0 is in quadrant 1
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the exact value of sin 20 if sin0= 4/5 and 0 is in quadrant 1
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Since sin(t) = 4/5 y = 4 and r = 5
Then x = sqrt[r^2-y^2] = sqrt[25-16] = 3
So cos(t) = 3/5
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Ans: sin(2t) = 2*sin(t)*cos(t) = 2(4/5)(3/5) = 24/25
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Cheers,
Stan H.
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