-1/3 = cos 2theta = 1 - 2 sin^2 theta
2 sin^2 theta = 4/3
sin theta = sqrt(2/3)
cos theta = sqrt(1 - 2/3) = -sqrt(1/3)
(minus since theta must be in quadrant 2)
tan theta = -sqrt2
theta = 125.26 degrees
You draw the figure
if cos 2 theta = -(1/3) and theta is in Quadrant 2, find sin theta, cos theta, tan theta, and draw triangle theta
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