This is a common setup for kinematics problems in physics. My geometry is rusty and I want to understand this very simple idea.
I am having trouble understanding why the angle $\theta$ formed by $\overrightarrow{w}$ is equal to $\theta$ = $\angle$ BOA.
My initial ideas:
- If we extend $w$ we can get a right triangle and somehow prove the angles equal by similarity.
- Some sort of use of interior angles and parallel lines.