Question

Find and simplify the difference quotient f(x + h) − f(x)/h for the following function:
f(x) = x2 − 9x + 8

Answer 1

which part are your having trouble with?

Answer 2

all of it, i dont understand how to do it

Answer 3

f(x+h) is f(x) but with (x+h) plugged in as every x

so f(x+h) = (x+h)^2 - 9(x+h) + 8

you'll want to expand that and find [f(x+h) - f(x)]/h

Answer 4

so itd be x^2+h^2-9x-9h+8 ?

Answer 5

????

Answer 6

(x+h)^2 = x^2 + 2xh + h^2

but the rest is correct

Answer 7

okay but could you explain how you get 2xh?

Answer 8

when multiplying two binomials, you use FOIL:
[steps 1,2,3,4]