SOLUTION: if theta is in Quadrant II and cos theta = -3/4 , find an exact value for sin2 theta

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Question 972527: if theta is in Quadrant II and cos theta = -3/4 , find an exact value for sin2 theta
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
if theta is in Quadrant II and cos theta = -3/4 , find an exact value for sin2 theta
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cosx=-3/4
sinx=√(1-cos^2(x))=√(1-9/16)=√(7/16)=√7/4
sin2x=2sinxcosx=2*√7/4*-3/4=-(6√7)/16