1. The problem statement, all variables and given/known data Tanθ = 5/12 , with θ in Quadrant 1, find sin2θ? 2. Relevant equations 3. The attempt at a solution I drew a diagram in quadrant 1, it pretty much looked like a right triangle with a 5 for the length of the sin part and the 12 for the length of the cos part of the tan of 5/12 mentioned in the initial question. Then I noted that sin will be positive in the first quadrant. Now I'm having trouble coming up with the formula to use, I tried Sin2θ=2sinθcosθ which did not work.