Question

Help! Let f(x)= x^2-2x-3. Evaluate and simplify the following difference quotient.

f(2+h)-f(2)/h=?

Answer 1

It says evaluate, so plug those into the formula.
f(2) = (2)^2-2(2)-3
f(2+h) = (2+h)^2-2(2+h)-3
Expand and simplify those.

Answer 2

-3
h^2+2h-3

Where do I go from there?

Answer 3

Sorry not sure on the next step

Answer 4

h^2+2h-6?

Answer 5

You plug those values back into the original one.
[f(2+h)-f(2)]/h
[h^2+2h-3 - -3]/h
[h^2+2h]/h

Answer 6

If you cancel h in the numerator and denominator you should get h+2 as your answer.

Answer 7

Got it! thank you for explaining!