List of integrals of rational functions (original) (raw)

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The following is a list of integrals (antiderivative functions) of rational functions. Any rational function can be integrated by partial fraction decomposition of the function into a sum of functions of the form:

a ( x − b ) n {\displaystyle {\frac {a}{(x-b)^{n}}}} {\displaystyle {\frac {a}{(x-b)^{n}}}}, and a x + b ( ( x − c ) 2 + d 2 ) n . {\displaystyle {\frac {ax+b}{\left((x-c)^{2}+d^{2}\right)^{n}}}.} {\displaystyle {\frac {ax+b}{\left((x-c)^{2}+d^{2}\right)^{n}}}.}

which can then be integrated term by term.

For other types of functions, see lists of integrals.

Miscellaneous integrands

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Integrands of the form x m(a x + b)n

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Many of the following antiderivatives have a term of the form ln |ax + b|. Because this is undefined when x = −b / a, the most general form of the antiderivative replaces the constant of integration with a locally constant function.[1] However, it is conventional to omit this from the notation. For example, ∫ 1 a x + b d x = { 1 a ln ⁡ ( − ( a x + b ) ) + C − a x + b < 0 1 a ln ⁡ ( a x + b ) + C + a x + b > 0 {\displaystyle \int {\frac {1}{ax+b}}\,dx={\begin{cases}{\dfrac {1}{a}}\ln(-(ax+b))+C^{-}&ax+b<0\\{\dfrac {1}{a}}\ln(ax+b)+C^{+}&ax+b>0\end{cases}}} {\displaystyle \int {\frac {1}{ax+b}}\,dx={\begin{cases}{\dfrac {1}{a}}\ln(-(ax+b))+C^{-}&ax+b<0\\{\dfrac {1}{a}}\ln(ax+b)+C^{+}&ax+b>0\end{cases}}}is usually abbreviated as ∫ 1 a x + b d x = 1 a ln ⁡ | a x + b | + C , {\displaystyle \int {\frac {1}{ax+b}}\,dx={\frac {1}{a}}\ln \left|ax+b\right|+C,} {\displaystyle \int {\frac {1}{ax+b}}\,dx={\frac {1}{a}}\ln \left|ax+b\right|+C,}where C is to be understood as notation for a locally constant function of x. This convention will be adhered to in the following.

Integrands of the form x m / (_a x_2 + b x + c)n

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For a ≠ 0 : {\displaystyle a\neq 0:} {\displaystyle a\neq 0:}

Integrands of the form x m (a + b x n)p

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Integrands of the form (A + B x) (a + b x)m (c + d x)n (e + f x)p

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Integrands of the form x m (A + B x n) (a + b x n)p (c + d x n)q

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Integrands of the form (d + e x)m (a + b x + _c x_2)p when _b_2 − 4 a c = 0

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Integrands of the form (d + e x)m (A + B x) (a + b x + _c x_2)p

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Integrands of the form x m (a + b x n + c x_2_n)p when _b_2 − 4 a c = 0

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Integrands of the form x m (A + B x n) (a + b x n + c x_2_n)p

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  1. ^ "Reader Survey: log|x| + C", Tom Leinster, The n_-category Café_, March 19, 2012