Based on what you have just said, I think you are doing calculus problems. I need to see the full problem statement in order to know how to approach the problem as you initially described it. OK?

OK. if f(x) = 1/(3x), then f(x+h) = 1/3(x+h) and the DIFFERENCE is then f(x+h) - f(x). The difference QUOTIENT is then [f(x+h) - f(x)] / h = [1/3(x+h) - 1/(3x)] / h. Do you need to simplify this?

That's perfect. this has helped me a great deal. I could do the other problems but not the ones with a denominator whew. I have my first test on Tuesday