# Thread: definite integral of a absolute value

1. ## definite integral of a absolute value

How do I intergrate this probelm?
intergel{ absolute value of (1-4x/1+3x)} dx
The professor said it was a simple algerbra trick but I'm not seeing it.

2. Recall $\displaystyle \int |x|dx = \frac{x|x|}{2}$

and $\displaystyle \frac{1-4x}{1+3x} = \frac{-4}{3}+\frac{7}{3(3x+1)}$

3. Originally Posted by joe45
How do I intergrate this probelm?
intergel{ absolute value of (1-4x/1+3x)} dx.
We need to know the limits of integration. From what to what?