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appleduardo
whats the integral for x^4 / (1-x) ??
Try to get some common fractions from this integrand.
i would have written (x^4-1)+1 as numerator then separate the numerator,-[ (x^4-1)/(x-1) +1/(x-1)] 2nd term is easy to integrate. for 1st term, you can cancel out common factor of (x-1) from numerator and denominator.
if you know how to factorize x^4-1
Hint:\[x^4=x^4-1+1=(x^2-1)(x^2+1)+1=(x-1)(x+1)(x^2+1)-1.\]
or make a substitution as u=1-x