# Evaluating the Difference Quotient

## Homework Statement

Evaluate the difference quotient of:
f(1+h)-f(1) / h
if f(x)=x3

## The Attempt at a Solution

I took the derivative of x3 to be 3x2 and solved for when x=1 (given from the difference quotient) and got 3, but when I enter the value it's marked incorrect. Not sure what I'm doing wrong, unless I just interpreted the question the wrong way.

pasmith
Homework Helper

## Homework Statement

Evaluate the difference quotient of:
f(1+h)-f(1) / h
if f(x)=x3

## The Attempt at a Solution

I took the derivative of x3 to be 3x2 and solved for when x=1 (given from the difference quotient) and got 3, but when I enter the value it's marked incorrect. Not sure what I'm doing wrong, unless I just interpreted the question the wrong way.

Calculate $((1 + h)^3 - 1^3)/h$ and do not take the limit $h \to 0$.

• 1 person
Ah, okay. Got h^2+3h+3, entered it and it was correct. Thanks! I'm not sure why I thought it was asking for the limit, guess I'm still a little fuzzy from the summer.