Question

prove this vector identity: (u-v)dot(u+v) = ||u||^2-||v||^2

Answer 1

(u-v) dot (u+v)= |(u-v)| *|(u+v)| cos(theta)

Answer 2

so if you say theta is 0 then you have
(u-v) * (u+v) + u^2 - v^2

Answer 3

wooops sorry please replace that + with an =