# Homework Help: Evaluate improper integral

1. Apr 26, 2010

### annoymage

1. The problem statement, all variables and given/known data

evaluate

$$\int$$ $$\frac{1}{(1+x)\sqrt{x}}$$ dx

2. Relevant equations

N/A

3. The attempt at a solution

how to do this, i cant use partial fraction, and integration by part makes it harder i guess, maybe using substitution, but how T_T
helpp

Last edited: Apr 26, 2010
2. Apr 26, 2010

### Je m'appelle

Hi, do you have the answer?

3. Apr 26, 2010

### annoymage

no, why?

4. Apr 26, 2010

### Je m'appelle

I tried to solve it through substitution, but I'm not sure if it's correct and would like to have it verified.

5. Apr 26, 2010

### annoymage

can you tell me what substituion you are using please?

6. Apr 26, 2010

### Cyosis

When you have an integral like this always try a few substitutions instead of just staring at it. Obvious substitutions would be u=1+x and u=sqrt(x). I will let you decide which one is the useful one.

7. Apr 26, 2010

### Je m'appelle

I tried this:

$$u = \sqrt{x}$$

$$u^2 = x$$

Can you take over from here?

8. Apr 26, 2010

### annoymage

thanks, i got the idea. thank you very much