1. The problem statement, all variables and given/known data I was shown a formula by a physicist I met through a friend when I asked for help with a homework problem. I needed to find y final for a motion in 2 dimensions problem. He showed me this: Y1 = X1 * tan(Theta) + (Ay * X1^2) /( 2 * V0^2 * cos^2(Theta)) Y1 = Y final X1 = X Final Ay = Acceleration of Y V0 = Initial Velocity I would love to know where this comes from and how to derive it. The X1tan(theta) makes sense to me: that would just = y of a triangle with base of x1. But the cos^2 and X1 ^2 confuses me. Did those come from an identity? Have any of you seen this before?