How can I simplify this integral with a variable exponent in the denominator?

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SUMMARY

The integral discussed is \int(x^4+2x^2+x+1)/(x^2+1)^x. The solution approach involves recognizing that if the exponent on the denominator is indeed variable (as "x"), simplification is complex. However, if the exponent were a constant (like "2"), the recommended method is to divide the fraction into a polynomial and a proper fraction, specifically \frac{ax+b}{x^2+1}. This can be further split into \frac{ax}{x^2+1} and \frac{1}{x^2+1}, where the first part utilizes the substitution u=x^2+1 and the second part leads to an arctangent function.

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Homework Statement


[tex]\int(x^4+2x^2+x+1)/(x^2+1)^x[/tex]


The Attempt at a Solution


am I supposed to multiply out the denominator then do u sub?
 
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nevermind i think its arctan
 
It isn't anything if the exponent on that denominator is really "x"! If it was supposed to be "2", I recommend dividing the fraction our so that you have a polynomial plus a "proper fraction" of the form [tex]\frac{ax+ b}{x^2+ 1}[/tex]. That you divide into two parts: [tex]\frac{ax}{x^2+1}[/tex] and [tex]\frac{1}{x^2+ 1}[/tex]. The first uses the simple substitution [tex]u= x^2+ 1[/tex] and the second is an arctan.
 

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