# If #A = <2 ,1 ,-3 >#, #B = <3 ,4 ,1 ># and #C=A-B#, what is the angle between A and C?

##### 1 Answer

May 5, 2018

The angle is

#### Explanation:

Start by calculating

The angle between

Where

The dot product is

The modulus of

The modulus of

So,