Use PFD to solve:
$$\int\limits_{}^{}\frac{1}{(1+ x^2)(x)}dx$$

Question

Use PFD to solve:
$$\int\limits_{}^{}\frac{1}{(1+ x^2)(x)}dx$$

anonymous · Answer

PFD => Partial fraction decomposition

anonymous · Answer

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anonymous · Answer

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I do not know why it is saying I am typing a reply

anonymous · Answer

http://www.wolframalpha.com/input/?i=integral+1%2F%5B%281%2Bx%5E2%29%28x%29%5D I got confused at wolf's substitution

anonymous · Answer

pretty extensive list there.... :)

anonymous · Answer

$$\frac{1}{x \left( 1 + x^2 \right)} = \frac{A}{x} + \frac{Bx + C}{1 + x^2}$$$$1 = (A + B)x^2 + Cx + A$$$$A + B = 0$$$$C = 0$$$$A = 1$$solve for B$$B = -1$$and then the PFD is finished$$\frac{1}{x\left(1 + x^2\right)} = \frac{1}{x} - \frac{x}{1 + x^2}$$integrate it and its done

anonymous · Answer

Got it.