I cannot prove that the integral is 0

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The integral in question is suggested to be zero, and participants discuss various methods to prove this. A key insight is that the two functions involved are inverses of each other on the interval [0,1]. Several users propose using substitutions and properties of the gamma function, while others argue that the beta function is unnecessary for this specific case. The discussion emphasizes manipulating the integrals directly to demonstrate the result without invoking the beta function. Ultimately, the consensus is that the integral can indeed be shown to be zero through careful analysis of the functions involved.
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Homework Statement


Evaluate

http://img338.imageshack.us/img338/4931/52219436.png

Homework Equations


hint: the integral is zero.


The Attempt at a Solution


I don't know how to tackle this, can someone give me a hint please? I looked at several subsitutions and IBP's but I'm stuck.
 
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You can evaluate the integral in terms of the Euler Beta function. Use two different substitutions for each part and properties of the gamma function to show it's zero.
 
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Dick said:
You can evaluate the integral in terms of the Euler Beta function. Use two different substitutions for each part and properties of the gamma function to show it's zero.

The integral is in stewart's book problem plus section I very much doubt that the beta function needs to be invoked...
 


dirk_mec1 said:
The integral is in stewart's book problem plus section I very much doubt that the beta function needs to be invoked...

Then I would suggest you look at how the proof works in terms of the integral definition of the beta function and figure out how to do the same thing by manipulating the integrals without saying the words 'beta function'.
 


In this special case it can be done without the beta function. Note that the two given functions are each others inverses on the interval [0,1].
 


Cyosis said:
In this special case it can be done without the beta function. Note that the two given functions are each others inverses on the interval [0,1].

Nice observation!
 


Cyosis said:
In this special case it can be done without the beta function. Note that the two given functions are each others inverses on the interval [0,1].

This is what I've been waiting for.
 

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