Question 1053798
Find the exact values of sin 2u, cos 2u, and tan 2u using the double-angle formulas.cos u = &#8722; 15/17,  &#960;/2 < u < &#960;
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Find sin(u):
sin = sqrt(1 - cos^2) = +8/17 (+ in Q2)
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sin(2u) = 2*sin(u)*cos(u)
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Then cos(2u) = sqrt(1 - sin^2(2u))
Then tan(2u) = sin(2u)/cos(2u)