Question

How does one simplify
\[
u_1^2 + u_2^2 + u_3^2 + v_1^2 + v_2^2 + v_3^2 - 2 \| u\| \| v \| \cos{\theta}
\]
to
\[
\theta = \acos{\( \frac{u_1 v_1 + u_2 v_2 + u_3 v_3}{\|u\| \|v\|} \)}
\]

Answer 1

nvm