# Indefinite integral

• April 11th 2009, 05:28 PM
swimmergirl
Indefinite integral
I solved this but my answer differs from the correct answer in my solution manual

integral (x-1)^2

I expanded the integrand and got x^2-2x+1 so I separated the integral into three for each term and got the different answer.

The correct answer says (x-1)^3/3

Why didnt my method work?
• April 11th 2009, 05:31 PM
mr fantastic
Quote:

Originally Posted by swimmergirl
I solved this but my answer differs from the correct answer in my solution manual

integral (x-1)^2

I expanded the integrand and got x^2-2x+1 so I separated the integral into three for each term and got the different answer.

The correct answer says (x-1)^3/3

Why didnt my method work?

If you have correctly done what you say you've done then your answer will factorise into the given answer.

Note: $\int \! (ax + b)^n \, dx = \frac{1}{a} \cdot \frac{1}{(n+1)} (ax + b)^{n+1} + C$ provided $n \neq -1$.