Finding the value of integral.

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Homework Statement


$$ \int_0^{\pi} \frac{x(sinx)^{2n}}{(sinx)^{2n}+(cosx)^{2n}} $$ =
A) π2
B) 2π2
C) π2/4
D) π/2

Homework Equations


$$ \int_0^π f(x)dx = \int_0^π f(a-x)dx $$

The Attempt at a Solution


If we put n = 1, we get the C option π2/4
But is it true for all n?
 
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Remember that ##\int_0^{2a} f(x)dx=2\int_0^a f(x)dx## iff ##f(2a-x)=f(x)## and then consider the integral ##\int_0^{\pi} \frac{(sinx)^{2n}}{(sinx)^{2n}+(cosx)^{2n}}## using the rule you mentioned.
 
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certainly said:
Remember that ##\int_0^{2a} f(x)dx=2\int_0^a f(x)dx## iff ##f(2a-x)=f(x)## and then consider the integral ##\int_0^{\pi} \frac{(sinx)^{2n}}{(sinx)^{2n}+(cosx)^{2n}}## using the rule you mentioned.
Thanks, I got it certainly Calculus Cuthbert.:smile:
 
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muffins from the cupboard ? no, no dear fellow I'm not hungry.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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