Sing the definition of the derivative, find f'(x). then find f'(1), f'(2), and f'(3)when the derivative exists. f(x)=-x^2+4x-9

By definition of the derivative, and with , we have

In this case,

Then

so that as , we're left with

and so

step-by-step explanation: i dont

4932,9180,7625 are divisible by 9