]> Exercise 3.3

## Exercise 3.3

Express the square of the component of $v ⟶$ in the direction of $w ⟶$ in terms of dot products.

Solution:

By definition this square is $| v ⟶ | 2 cos ⁡ 2 θ$ where $θ$ is the angle between $v ⟶$ and $w ⟶$ , which is $( v ⟶ , w ⟶ ) 2 ( w ⟶ , w ⟶ )$ .