Calculating Integral: ##\int_a^b x\left(\frac{b-x}{b-a}\right)^{n-1} \; dx##

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Homework Statement


How do I calculate ##\int_a^b x\left(\frac{b-x}{b-a}\right)^{n-1} \; dx##?

Homework Equations

The Attempt at a Solution


I tried the substitution ##u = \frac{b-x}{b-a}## to no avail. Someone please help.
 
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squenshl said:

Homework Statement


How do I calculate ##\int_a^b x\left(\frac{b-x}{b-a}\right)^{n-1} \; dx##?

Homework Equations

The Attempt at a Solution


I tried the substitution ##u = \frac{b-x}{b-a}## to no avail. Someone please help.
That substitution should work: show us what went wrong when you tried it.
A little hint: don't bother with the ##b-a## in the denominator, as that is a constant. Set ##u=b-x##.
EDIT: it doesn't really matter, both substitutions work just fine.
 
Last edited:
Samy_A said:
That substitution should work: show us what went wrong when you tried it.
A little hint: don't bother with the ##b-a## in the denominator, as that is a constant. Set ##u=b-x##.
EDIT: it doesn't really matter, both substitutions work just fine.
Thanks a lot. I got it.
 
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