Theoretical Range Equation Derivation

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ccsmarty
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Homework Statement



Derive an expression for calculating the theoretical range of the ball in terms of y, g, theta, and v0.

Homework Equations



Set of kinematic equations in plain text and LaTeX-style layout: v = v0 + at; x = x0 + v0t + (1/2)at^2; v^2 = v0^2 + 2a(x - x0); x - x0 = ((v0 + v)/2)t; v0x = v0 cos theta; v0y = v0 sin theta.


The Attempt at a Solution



I've tried just about everything to figure this out. I started with the motion in the x-direction, and plugged the second-to-last equation in for v0x in the second equation, and then solved for "t". Then I plugged the "t" into the second equation (but for the y-direction), and tried solving for "x". But I kept getting really weird numbers. Can someone please help me out?
 
Motion in the x direction is at a constant speed, so what you are looking for is the time given by motion in the y direction.
Use s = ut + 1/2 at^2 and v^2 = u^2 + 2as to get an equation for time as a function of initial vertical velocity component. Remember that final (vertical) velocity is zero at the top of the curve.
Then plug this into the horizontal component of velocity to get a range.