Unit Vector Along a Given Vector

Unit Vector Along a Given Vector

If:

$$\vec a=a_1\hat i+a_2\hat j+a_3\hat k$$

then the unit vector along $$\vec a$$ is:

$$\hat a=\frac{a_1\hat i+a_2\hat j+a_3\hat k}{\sqrt{a_1^2+a_2^2+a_3^2}}$$

Usage

- Used when a question asks for the unit vector in a specified direction.