# If #A = <2 ,-7 ,5 >#, #B = <5 ,-7 ,-1 ># and #C=A-B#, what is the angle between A and C?

##### 1 Answer

Nov 2, 2016

The angle is

#### Explanation:

The angle between 2 vectors is given by the dot product.

If we have two vectors

is given by

The dot product

The modulus of

The modulus of

So