# Derivation of Physics Equation

posted by
**Anonymous**
.

How do we derive these laws: (most of the time, the numbers are subscript)

v'2 = v1 * ( (2 * m) / (m1 + m2) ) + v2 * ( (m2-m1) / (m1+m2) )

&

v'1 = v1 * ( (m1-m2) / (m1+m2) ) + v2 * ( (2 * m2) / (m1 + m2) )