MHB Solving the Integral: $\int_{0}^{1}\dfrac{x^4(1-x)^4}{1+x^2}dx$

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\[\int_{0}^{1}\dfrac{x^4(1-x)^4}{1+x^2}dx=?\]
 
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Albert said:
\[\int_{0}^{1}\dfrac{x^4(1-x)^4}{1+x^2}dx=?\]

expanding we get

$x^6-4x^5+5x^4-4x^2+4-\frac{4}{1+x^2}$

integrating we get

$\frac{x^7}{7} – \frac{2}{3}x^6+ x^5-\frac{4}{3}x^3 + 4x – 4\arctan x$

x=1 gives $\frac{1}{7} – \frac{2}{3}+1-\frac{4}{3} + 4 – \pi = \frac{22}{7}- \pi$ and at x =0 it is zero hence the integral is $\frac{22}{7}- \pi$
 
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kaliprasad said:
expanding we get

$x^6-4x^5+5x^4-4x^2+4-\frac{4}{1+x^2}$

integrating we get

$\frac{x^7}{7} – \frac{2}{3}x^6+ x^5-\frac{4}{3}x^2 + 4x – 4\arctan x$

x=1 gives $\frac{1}{7} – \frac{2}{3}+1-\frac{4}{3} + 4 – \pi = \frac{22}{7}- \pi$ and at x =0 it is zero hence the integral is $\frac{22}{7}- \pi$
answer correct , a typo exists in your intergrating
 
Albert said:
answer correct , a typo exists in your intergrating

thanks I have done the needful
 
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