# If #A = <7 ,-5 ,6 >#, #B = <4 ,-8 ,9 ># and #C=A-B#, what is the angle between A and C?

##### 1 Answer

Oct 13, 2016

#### Explanation:

Compute vector C:

Compute the dot-product of vectors A and C:

There is another form for the equation of the dot-product that contains the angle between the two vectors:

Compute the magnitude of vector A:

Compute the magnitude of vector C: