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Find $\\displaystyle \\int\\frac{ax^3+ax+b}{1+x^2}\\;dx$. Enter the constant of integration as $C$.

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Integrate the following function $f(x)$

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\\[f(x)=\\simplify[std]{({n}x^3+{n}x+{p})/(1+x^2)}\\]

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You may need to use the standard result $\\int \\frac{1}{1+x^2}dx = \\arctan{x}+C$

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Since the degree of the numerator of $f(x)$ is greater than the denominator, $f(x)$ is improper.

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First, perform a polynomial long division, so that $f(x)$ can be rewritten in the form $\\displaystyle{f(x)=\\simplify[std]{{n}x+{p}/(1+x^2)}}$.

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Each term of this expression can then be integrated using standard functions (to within the arbitrary constant) to give:

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$\\displaystyle{\\int f(x)\\;dx=\\simplify[std]{{n}x^2/2+{p}arctan(x)} +C}$

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 Input all numbers as fractions or integers and not as decimals.

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$\\displaystyle \\int f(x)\\;dx=\\;\\;$[[0]]

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You must input the arbitrary constant of integration as $C$.

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Also input all numbers as fractions or integers and not as decimals.

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