# How to derive this equation

by zeion
Tags: derive, equation
 P: 467 1. The problem statement, all variables and given/known data I wanted to know how this equation is derived. Thanks. 2. Relevant equations $${v_{f}}^2 = {v_{i}}^2 + 2a\Delta d$$ 3. The attempt at a solution $$v_{f} - v_{i} = \frac {\Delta d a} {\Delta v}$$
 P: 623 We have the two relations: $$t=\frac{v-u}{t}$$ $$s=\frac{1}{2}(u+v)t$$ Substitute the first into the second and the deed is done.