What is the antiderivative of:

(x - x^3) / (x^4 +1)?
I know that somehow I will need to factor out 1/(x^2 + 1), or the derivative of arctan, but I'm not quite sure how to do this. Any help is appreciated, thank you.

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partial fractions (x - x^3) / (x^4 +1)

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Then type:

integrate (x - x^3) / (x^4 +1)

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