Michael J. answered 08/31/17
Tutor
5
(5)
Effective High School STEM Tutor & CUNY Math Peer Leader
You will use the formula
f(x + h) - f(x)
_____________
h
Then apply f(x) to this difference quotient.
(x + h)2 + 6 - (x2 + 6)
__________________
h
Now just simplify. As you simplify, you should be able to cancel h from the denominator.