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| Question 1055399:  Find the exact values of sin 2u,cos 2u, and tan 2u using the double-angle formulas.
 tan u = 5/3,    0 < u < π/2
 Answer by Alan3354(69443)
      (Show Source): 
You can put this solution on YOUR website! Find the exact values of sin 2u,cos 2u, and tan 2u using the double-angle formulas. tan u = 5/3,    0 < u < π/2
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 tan(u) = y/x
 r = sqrt(x^2 + y^2) = sqrt(34)
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 sin(u) = y/r = 5sqrt(34)/34
 cos(u) = x/r = 3sqrt(34)/34
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 sin(2u) = 2sin(u)*cos(u)
 cos(2u) = sqrt(1 - sin^2(2u))
 tan(2u) = sin(2u)/cos(2u)
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 In Q2,
 sin is +
 cos is -
 tan is -
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