1. The problem statement, all variables and given/known data A projectile is launched from the earth’s surface at initial speed vi at angle θ0 with the horizontal. When the projectile is at its maximum height h, it has half the speed it had when it was at half its maximum height h/2 At what angle was the projectile launched? 2. Relevant equations 3. The attempt at a solution I know that the velocity vector at the highest point is vicosθ, and I know that the maximum height of the parabola is (visinθ)2 / 2g. At this point, I don't really know where to go. I'm not sure how to relate height and velocity together with what I know. I was doing this earlier and I tried to go further, but I just ended up with a lot of variable/trig function couples that don't make sense. I could take a picture of all the work I've done, but you wouldn't be able to follow it. I barely know what I tried. You don't really have to answer it for me, just what should the next step be?