Please Find the difference quotient


f(x+h)-fx/h for f(x)= 4x-9 and simplify

3 answers

put x+h in f(x) to get 4x+4h-9
then subtract 4x+9 then divide by h
This is what I got, is it correct? Thanks!

4x+4h-9+ (-4x+9)/h
4x-4x= 4h-9+9/h
= 4h/h
=4
Your answer is correct, but it is preferable to place parentheses where they are needed to avoid ambiguity, for example:

(4x+4h-9+ (-4x+9))/h
(4x-4x + 4h-9+9)/h
= 4h/h
=4