I don't understand what I'm doing wrong in this problem it says find the indicated value for the given function. It is f(x)=3x^2-5x+8. there is a blank for the answer equals f(a+h)-f(a)/h. can anyone help ?

What are you supposed to do?

Use the defition of a derivative?

If so,

\lim_{h\to 0}\frac{3(x+h)^{2}-5(x+h)+8-(3x^{2}-5x+8)}{h}

Evalauting the limit will result in the derivative of f(x).

I am guessing here because your description is somehwat vague.

If this is not what you mean, please elaborate.

I don't know the problem, but go on YouTube, type in yourteacher.com / whatever you want to know, and a vid will pop up giving you step by step how to do that kind of problem

If you don't contribute to the thread, don't post please and if you like yourteacher.com, what are you doing here?