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:
[math]\displaystyle{ \frac{a}{(x-b)^n} }[/math], and [math]\displaystyle{ \frac{ax + b}{\left((x-c)^2+d^2\right)^n}. }[/math]
which can then be integrated term by term.
For other types of functions, see lists of integrals.
Contents
1Miscellaneous integrands
2Integrands of the form xm(a x + b)n
3Integrands of the form xm / (a x2 + b x + c)n
4Integrands of the form xm (a + b xn)p
5Integrands of the form (A + B x) (a + b x)m (c + d x)n (e + f x)p
6Integrands of the form xm (A + B xn) (a + b xn)p (c + d xn)q
7Integrands of the form (d + e x)m (a + b x + c x2)p when b2 − 4 a c = 0
8Integrands of the form (d + e x)m (A + B x) (a + b x + c x2)p
9Integrands of the form xm (a + b xn + c x2n)p when b2 − 4 a c = 0
10Integrands of the form xm (A + B xn) (a + b xn + c x2n)p
11References
Miscellaneous integrands
[math]\displaystyle{ \int\frac{f'(x)}{f(x)} \, dx= \ln\left| f(x)\right| + C }[/math]
[math]\displaystyle{ \int\frac{1}{x^2+a^2} \, dx = \frac{1}{a}\arctan\frac{x}{a}\,\! + C }[/math]
[math]\displaystyle{ \int\frac{1}{x^2-a^2} \, dx = \frac{1}{2a}\ln\left|\frac{x-a}{x+a}\right| + C = \begin{cases} \displaystyle -\frac{1}{a}\,\operatorname{artanh}\frac{x}{a} + C = \frac{1}{2a}\ln\frac{a-x}{a+x} + C & \text{(for }|x| \lt |a|\mbox{)} \\[12pt] \displaystyle -\frac{1}{a}\,\operatorname{arcoth}\frac{x}{a} + C = \frac{1}{2a}\ln\frac{x-a}{x+a} + C & \text{(for }|x| \gt |a| \mbox{)} \end{cases} }[/math]
[math]\displaystyle{ \int\frac{1}{a^2-x^2} \, dx = \frac{1}{2a}\ln\left|\frac{a+x}{a-x}\right| + C = \begin{cases} \displaystyle \frac{1}{a}\,\operatorname{artanh}\frac{x}{a} + C = \frac{1}{2a}\ln\frac{a+x}{a-x} + C & \text{(for }|x| \lt |a|\mbox{)} \\[12pt] \displaystyle \frac{1}{a}\,\operatorname{arcoth}\frac{x}{a} + C = \frac{1}{2a}\ln\frac{x+a}{x-a} + C & \text{(for }|x| \gt |a| \mbox{)} \end{cases} }[/math]
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,
[math]\displaystyle{ \int\frac{1}{ax + b} \, dx= \begin{cases}
\dfrac{1}{a}\ln(-(ax + b)) + C^- & ax+b\lt 0 \\
\dfrac{1}{a}\ln(ax + b) + C^+ & ax+b\gt 0
\end{cases} }[/math]
is usually abbreviated as
[math]\displaystyle{ \int\frac{1}{ax + b} \, dx= \frac{1}{a}\ln\left|ax + b\right| + C, }[/math]
where C is to be understood as notation for a locally constant function of x. This convention will be adhered to in the following.
[math]\displaystyle{ \int\frac{1}{ax^2+bx+c} dx =
\begin{cases}
\displaystyle \frac{2}{\sqrt{4ac-b^2}}\arctan\frac{2ax+b}{\sqrt{4ac-b^2}} + C & \text{(for }4ac-b^2\gt 0\mbox{)} \\[12pt]
\displaystyle \frac{1}{\sqrt{b^2-4ac}}\ln\left|\frac{2ax+b-\sqrt{b^2-4ac}}{2ax+b+\sqrt{b^2-4ac}}\right| + C =
\begin{cases}
\displaystyle -\frac{2}{\sqrt{b^2-4ac}}\,\operatorname{artanh}\frac{2ax+b}{\sqrt{b^2-4ac}} + C &\text{(for }|2ax+b|\lt \sqrt{b^2-4ac}\mbox{)} \\[6pt]
\displaystyle -\frac{2}{\sqrt{b^2-4ac}}\,\operatorname{arcoth}\frac{2ax+b}{\sqrt{b^2-4ac}} + C &\text{(else)}
\end{cases}
& \text{(for }4ac-b^2\lt 0\mbox{)} \\[12pt]
\displaystyle -\frac{2}{2ax+b} + C & \text{(for }4ac-b^2=0\mbox{)}
\end{cases} }[/math]
[math]\displaystyle{ \int\frac{x}{ax^2+bx+c} \, dx = \frac{1}{2a}\ln\left|ax^2+bx+c\right|-\frac{b}{2a}\int\frac{dx}{ax^2+bx+c} + C }[/math]
[math]\displaystyle{ \int\frac{mx+n}{ax^2+bx+c} \, dx = \begin{cases}
\displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|+\frac{2an-bm}{a\sqrt{4ac-b^2}}\arctan\frac{2ax+b}{\sqrt{4ac-b^2}} + C &\text{(for }4ac-b^2\gt 0\mbox{)} \\[12pt] \displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|+\frac{2an-bm}{2a\sqrt{b^2-4ac}}\ln\left|\frac{2ax+b-\sqrt{b^2-4ac}}{2ax+b+\sqrt{b^2-4ac}}\right| + C =
\begin{cases}
\displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|-\frac{2an-bm}{a\sqrt{b^2-4ac}}\,\operatorname{artanh}\frac{2ax+b}{\sqrt{b^2-4ac}} + C &\text{(for }|2ax+b|\lt \sqrt{b^2-4ac}\mbox{)} \\[6pt]
\displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|-\frac{2an-bm}{a\sqrt{b^2-4ac}}\,\operatorname{arcoth}\frac{2ax+b}{\sqrt{b^2-4ac}} + C &\text{(else)}
\end{cases}
& \text{(for }4ac-b^2\lt 0\mbox{)} \\[12pt]
\displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|-\frac{2an-bm}{a(2ax+b)} + C = \frac{m}{a}\ln\left|x+\frac{b}{2a}\right|-\frac{2an-bm}{a(2ax+b)} + C &\text{(for }4ac-b^2=0\mbox{)}\end{cases} }[/math]
[math]\displaystyle{ \int\frac{1}{(ax^2+bx+c)^n} \, dx= \frac{2ax+b}{(n-1)(4ac-b^2)(ax^2+bx+c)^{n-1}}+\frac{(2n-3)2a}{(n-1)(4ac-b^2)}\int\frac{1}{(ax^2+bx+c)^{n-1}} \, dx + C }[/math]
[math]\displaystyle{ \int\frac{x}{(ax^2+bx+c)^n} \, dx= -\frac{bx+2c}{(n-1)(4ac-b^2)(ax^2+bx+c)^{n-1}}-\frac{b(2n-3)}{(n-1)(4ac-b^2)}\int\frac{1}{(ax^2+bx+c)^{n-1}} \, dx + C }[/math]
[math]\displaystyle{ \int\frac{1}{x(ax^2+bx+c)} \, dx= \frac{1}{2c}\ln\left|\frac{x^2}{ax^2+bx+c}\right|-\frac{b}{2c}\int\frac{1}{ax^2+bx+c} \, dx + C }[/math]
Integrands of the form xm (a + b xn)p
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m and p toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Integrands of the form (A + B x) (a + b x)m (c + d x)n (e + f x)p
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m, n and p toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Special cases of these reductions formulas can be used for integrands of the form [math]\displaystyle{ (a+b\,x)^m (c+d\,x)^n (e+f\,x)^p }[/math] by setting B to 0.
Integrands of the form xm (A + B xn) (a + b xn)p (c + d xn)q
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m, p and q toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Special cases of these reductions formulas can be used for integrands of the form [math]\displaystyle{ \left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^q }[/math] and [math]\displaystyle{ x^m\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^q }[/math] by setting m and/or B to 0.
Integrands of the form (d + e x)m (a + b x + c x2)p when b2 − 4 a c = 0
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m and p toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Special cases of these reductions formulas can be used for integrands of the form [math]\displaystyle{ \left(a+b\,x+c\,x^2\right)^p }[/math] when [math]\displaystyle{ b^2-4\,a\,c=0 }[/math] by setting m to 0.
Integrands of the form (d + e x)m (A + B x) (a + b x + c x2)p
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m and p toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Special cases of these reductions formulas can be used for integrands of the form [math]\displaystyle{ \left(a+b\,x+c\,x^2\right)^p }[/math] and [math]\displaystyle{ (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^p }[/math] by setting m and/or B to 0.
Integrands of the form xm (a + b xn + c x2n)p when b2 − 4 a c = 0
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m and p toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Special cases of these reductions formulas can be used for integrands of the form [math]\displaystyle{ \left(a+b\,x^n+c\,x^{2 n}\right)^p }[/math] when [math]\displaystyle{ b^2-4\,a\,c=0 }[/math] by setting m to 0.
Integrands of the form xm (A + B xn) (a + b xn + c x2n)p
The resulting integrands are of the same form as the original integrand, so these reduction formulas can be repeatedly applied to drive the exponents m and p toward 0.
These reduction formulas can be used for integrands having integer and/or fractional exponents.
Special cases of these reductions formulas can be used for integrands of the form [math]\displaystyle{ \left(a+b\,x^n+c\,x^{2 n}\right)^p }[/math] and [math]\displaystyle{ x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p }[/math] by setting m and/or B to 0.