SOLUTION: If cos (Theta) = 3/5 and 0 < Theta <90 then find sin 4 (Theta)

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Question 167837: If cos (Theta) = 3/5 and 0 < Theta <90 then find

sin 4 (Theta)
Answer by gonzo(654) About Me  (Show Source):
You can put this solution on YOUR website!
cos (theta) = 3/5 = .6
theta = 53.130... degrees.
sin (4*theta) = sin (212.520 degrees) = -.5376
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i used the calculator to get the angle whose cosine was .6.
since that angle was between 0 and 90, i used it directly.
i then multiplied that angle * 4.
then i used the calculator to get the sine of that angle.
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i assumed you meant sin (4*theta) when you showed "sin 4 (theta)"
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