# Homework Help: Improper integrals

1. May 3, 2013

### aaaa202

1. The problem statement, all variables and given/known data
Check if the following integrals diverge:
Int(1/(x^3-2x^2+x), from 0 to 1) and Int(1/(x^3+x^2-2x)

2. Relevant equations
Ratio-test(not sure if thats the name)

3. The attempt at a solution
I have solved the problem and found that both integrals diverge at x=0. I just want to check if you guys agree with me.

2. May 3, 2013

### MostlyHarmless

Ratio test is for infinite series, not a improper integrals. It would be helpful to see your work.

3. May 3, 2013

### Staff: Mentor

Both integrands are undefined at x = 0, which is why the integrals are improper. Both integrands are also undefined at the other endpoint, x = 1.

You need to use limits to evaluate these integrals - then you can decide whether either one diverges.

4. May 4, 2013

### aaaa202

Okay ratio test was then not the correct name. What I did was use the test that if limx->0[g/f>0] then g also diverges if f diverges. So I took f as 1/x^3. Isn't this correct, and dont you guys get that both integrals diverge?

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