# A question of taking integral

1. Sep 17, 2011

### peace-Econ

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

Solve the integral.

2. Relevant equations

Integral: (x^m)*(1-x)^k where m is a nonnegative integer and k > -1

3. The attempt at a solution

I've tried to take this integral by using integral by parts, but I couldn't take it. Can anyone tell me how to take this integral? I really appreciate that.

2. Sep 18, 2011

### Dick

If it's an indefinite integral then that's an incomplete beta function. You can do a lot of things with it, but you can't write a simple elementary form for it. What do they really want you to do?

3. Sep 18, 2011

### peace-Econ

Sorry. the integral is actually 1 to 0. This question is actually induction.

Integral(1-0): (x^m)*(1-x)^k=n!/(k+1)(k+2).....(K+m+1) where m is a nonnegative integer and k > -1

So, I thought that if I take integral from the right side, I can prove it. But it does not seem the case...

4. Sep 18, 2011

### Dick

Then start working on the integration by parts idea. Call your integral I(m,k). Work out m=0. For practice try doing small values of m (m=1, m=2, m=3) until you see what's going on. Then try to express I(m+1,k) in terms of I(m,k) and apply induction.

Last edited: Sep 18, 2011
5. Sep 18, 2011

### peace-Econ

actually, I think I made it. Thanks!