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The following is a list of [[integral]]s ([[antiderivative]] functions) of [[rational function]]s. | |||
For other types of functions, see [[lists of integrals]]. | |||
<!--CAUTION: before 'correcting' one of these integrals, please check that the amended integral doesn't simply differ from the existing version by a constant term. NOTE: a constant *factor* in the argument of ln() may amount to a constant term in the integral. --> | |||
== Miscellaneous integrands == | |||
:<math>\int\frac{f'(x)}{f(x)} \, dx= \ln\left|f(x)\right| + C</math> | |||
:<math>\int\frac{1}{x^2+a^2} \, dx = \frac{1}{a}\arctan\frac{x}{a}\,\! + C</math> | |||
:<math>\int\frac{1}{x^2-a^2} \, dx = \begin{cases} \displaystyle -\frac{1}{a}\,\operatorname{arctanh}\frac{x}{a} = \frac{1}{2a}\ln\frac{a-x}{a+x} + C & \text{(for }|x| < |a|\mbox{)} \\[12pt] \displaystyle -\frac{1}{a}\,\operatorname{arccoth}\frac{x}{a} = \frac{1}{2a}\ln\frac{x-a}{x+a} + C & \text{(for }|x| > |a| \mbox{)} \end{cases}</math> | |||
: <math>\int \frac{dx}{x^{2^n} + 1} = \sum_{k=1}^{2^{n-1}} \left \{ \frac{1}{2^{n-1}} \left [ \sin \left(\frac{(2k -1) \pi}{2^n}\right) \arctan\left[\left(x - \cos \left(\frac{(2k -1) \pi}{2^n} \right) \right ) \csc \left(\frac{(2k -1) \pi}{2^n} \right) \right] \right] - \frac{1}{2^n} \left [ \cos \left(\frac{(2k -1) \pi}{2^n} \right) \ln \left | x^2 - 2 x \cos \left(\frac{(2k -1) \pi}{2^n} \right) + 1 \right | \right ] \right \} + C </math> | |||
<br /> | |||
Any rational function can be integrated using '''[[partial fractions in integration]]''', by decomposing the rational function into a sum of functions of the form: | |||
: <math>\frac{a}{(x-b)^n}</math>, and <math>\frac{ax + b}{\left((x-c)^2+d^2\right)^n}.</math> | |||
== Integrands of the form ''x''<sup>''m''</sup>(''a x'' + ''b'')<sup>''n''</sup> == | |||
:<math>\int\frac{1}{ax + b} \, dx= \frac{1}{a}\ln\left|ax + b\right| + C</math> | |||
::More generally,<ref>"[http://golem.ph.utexas.edu/category/2012/03/reader_survey_logx_c.html Reader Survey: log|''x''| + ''C'']", Tom Leinster, ''The ''n''-category Café'', March 19, 2012</ref> | |||
::<math>\int\frac{1}{ax + b} \, dx= \begin{cases} | |||
\frac{1}{a}\ln\left|ax + b\right| + C^- & x < -b/a \\ | |||
\frac{1}{a}\ln\left|ax + b\right| + C^+ & x > -b/a | |||
\end{cases}</math> | |||
:<math>\int (ax + b)^n \, dx= \frac{(ax + b)^{n+1}}{a(n + 1)} + C \qquad\text{(for } n\neq -1\mbox{)}\,\!</math> ([[Cavalieri's quadrature formula]]) | |||
<br> | |||
:<math>\int\frac{x}{ax + b} \, dx= \frac{x}{a} - \frac{b}{a^2}\ln\left|ax + b\right| + C</math> | |||
:<math>\int\frac{x}{(ax + b)^2} \, dx= \frac{b}{a^2(ax + b)} + \frac{1}{a^2}\ln\left|ax + b\right| + C</math> | |||
:<math>\int\frac{x}{(ax + b)^n} \, dx= \frac{a(1 - n)x - b}{a^2(n - 1)(n - 2)(ax + b)^{n-1}} + C \qquad\text{(for } n\not\in \{1, 2\}\mbox{)}</math> | |||
:<math>\int x(ax + b)^n \, dx= \frac{a(n + 1)x - b}{a^2(n + 1)(n + 2)} (ax + b)^{n+1} + C \qquad\text{(for }n \not\in \{-1, -2\}\mbox{)}</math> | |||
<br> | |||
:<math>\int\frac{x^2}{ax + b} \, dx= \frac{b^2\ln(\left|ax + b\right|)}{a^3}+\frac{ax^2 - 2bx}{2a^2} + C</math> | |||
:<math>\int\frac{x^2}{(ax + b)^2} \, dx= \frac{1}{a^3}\left(ax - 2b\ln\left|ax + b\right| - \frac{b^2}{ax + b}\right) + C</math> | |||
:<math>\int\frac{x^2}{(ax + b)^3} \, dx= \frac{1}{a^3}\left(\ln\left|ax + b\right| + \frac{2b}{ax + b} - \frac{b^2}{2(ax + b)^2}\right) + C</math> | |||
:<math>\int\frac{x^2}{(ax + b)^n} \, dx= \frac{1}{a^3}\left(-\frac{(ax + b)^{3-n}}{(n-3)} + \frac{2b (ax + b)^{2-n}}{(n-2)} - \frac{b^2 (ax + b)^{1-n}}{(n - 1)}\right) + C \qquad\text{(for } n\not\in \{1, 2, 3\}\mbox{)}</math> | |||
<br> | |||
:<math>\int\frac{1}{x(ax + b)} \, dx = -\frac{1}{b}\ln\left|\frac{ax+b}{x}\right| + C</math> | |||
:<math>\int\frac{1}{x^2(ax+b)} \, dx = -\frac{1}{bx} + \frac{a}{b^2}\ln\left|\frac{ax+b}{x}\right| + C</math> | |||
:<math>\int\frac{1}{x^2(ax+b)^2} \, dx = -a\left(\frac{1}{b^2(ax+b)} + \frac{1}{ab^2x} - \frac{2}{b^3}\ln\left|\frac{ax+b}{x}\right|\right) + C</math> | |||
== Integrands of the form ''x''<sup>''m''</sup> / (''a x''<sup>2</sup> + ''b x'' + ''c'')<sup>''n''</sup> == | |||
For <math>a\neq 0:</math> | |||
<br> | |||
:<math>\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>0\mbox{)} \\[12pt] | |||
\displaystyle -\frac{2}{\sqrt{b^2-4ac}}\,\mathrm{arctanh}\frac{2ax+b}{\sqrt{b^2-4ac}} + C = \frac{1}{\sqrt{b^2-4ac}}\ln\left|\frac{2ax+b-\sqrt{b^2-4ac}}{2ax+b+\sqrt{b^2-4ac}}\right| + C & \text{(for }4ac-b^2<0\mbox{)} \\[12pt] | |||
\displaystyle -\frac{2}{2ax+b} + C & \text{(for }4ac-b^2=0\mbox{)} | |||
\end{cases}</math> | |||
<br> | |||
:<math>\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> | |||
<br> | |||
:<math>\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>0\mbox{)} \\[12pt] \displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|-\frac{2an-bm}{a\sqrt{b^2-4ac}}\,\mathrm{arctanh}\frac{2ax+b}{\sqrt{b^2-4ac}} + C &\text{(for }4ac-b^2<0\mbox{)} \\[12pt] \displaystyle \frac{m}{2a}\ln\left|ax^2+bx+c\right|-\frac{2an-bm}{a(2ax+b)} + C &\text{(for }4ac-b^2=0\mbox{)}\end{cases}</math> | |||
<br> | |||
: <math>\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> | |||
<br> | |||
: <math>\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> | |||
<br> | |||
: <math>\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 ''x''<sup>''m''</sup> (''a'' + ''b x''<sup>''n''</sup>)<sup>''p''</sup> == | |||
* 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. | |||
:<math> | |||
\int x^m \left(a+b\,x^n\right)^p dx = | |||
\frac{x^{m+1} \left(a+b\,x^n\right)^p}{m+n\,p+1}\,+\, | |||
\frac{a\,n\,p}{m+n\,p+1}\int x^m \left(a+b\,x^n\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n\right)^p dx = | |||
-\frac{x^{m+1} \left(a+b\,x^n\right)^{p+1}}{a\,n (p+1)}\,+\, | |||
\frac{m+n (p+1)+1}{a\,n (p+1)}\int x^m \left(a+b\,x^n\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n\right)^p dx = | |||
\frac{x^{m+1} \left(a+b\,x^n\right)^p}{m+1}\,-\, | |||
\frac{b\,n\,p}{m+1}\int x^{m+n} \left(a+b\,x^n\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n\right)^p dx = | |||
\frac{x^{m-n+1} \left(a+b\,x^n\right)^{p+1}}{b\,n (p+1)}\,-\, | |||
\frac{m-n+1}{b\,n (p+1)}\int x^{m-n} \left(a+b\,x^n\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n\right)^p dx = | |||
\frac{x^{m-n+1} \left(a+b\,x^n\right)^{p+1}}{b (m+n\,p+1)}\,-\, | |||
\frac{a (m-n+1)}{b (m+n\,p+1)}\int x^{m-n}\left(a+b\,x^n\right)^pdx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n\right)^p dx = | |||
\frac{x^{m+1} \left(a+b\,x^n\right)^{p+1}}{a (m+1)}\,-\, | |||
\frac{b (m+n (p+1)+1)}{a (m+1)}\int x^{m+n}\left(a+b\,x^n\right)^pdx | |||
</math> | |||
== Integrands of the form (''A'' + ''B x'') (''a'' + ''b x'')<sup>''m''</sup> (''c'' + ''d x'')<sup>''n''</sup> (''e'' + ''f x'')<sup>''p''</sup> == | |||
* 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>(a+b\,x)^m (c+d\,x)^n (e+f\,x)^p</math> by setting ''B'' to 0. | |||
:<math> | |||
\int (A+B\,x) (a+b\,x)^m (c+d\,x)^n (e+f\,x)^p dx= | |||
-\frac{(A\,b-a\,B)(a+b\,x)^{m+1} (c+d\,x)^n(e+f\,x)^{p+1}}{b (m+1) (a\,f-b\,e)}\,+\, | |||
\frac{1}{b (m+1) (a\,f-b\,e)}\,\cdot | |||
</math><blockquote><math> | |||
\int (b\,c(m+1) (A\,f-B\,e)+(A\,b-a\,B) (n\,d\,e+c\,f(p+1))+d(b(m+1) (A\,f-B\,e)+f(n+p+1) (A\,b-a\,B))x)(a+b\,x)^{m+1} (c+d\,x)^{n-1}(e+f\,x)^p dx | |||
</math></blockquote> | |||
:<math> | |||
\int (A+B\,x) (a+b\,x)^m (c+d\,x)^n (e+f\,x)^p dx= | |||
\frac{B(a+b\,x)^m (c+d\,x)^{n+1}(e+f\,x)^{p+1}}{d\,f(m+n+p+2)}\,+\, | |||
\frac{1}{d\,f(m+n+p+2)}\,\cdot | |||
</math><blockquote><math> | |||
\int (A\,a\,d\,f(m+n+p+2)-B (b\,c\,e\,m+a(d\,e(n+1)+c\,f(p+1)))+(A\,b\,d\,f(m+n+p+2)+B (a\,d\,f\,m-b(d\,e(m+n+1)+c\,f(m+p+1)))) x)(a+b\,x)^{m-1} (c+d\,x)^n(e+f\,x)^p dx | |||
</math></blockquote> | |||
:<math> | |||
\int (A+B\,x) (a+b\,x)^m (c+d\,x)^n (e+f\,x)^p dx= | |||
\frac{(A\,b-a\,B)(a+b\,x)^{m+1} (c+d\,x)^{n+1}(e+f\,x)^{p+1}}{(m+1)(a\,d-b\,c)(a\,f-b\,e)}\,+\, | |||
\frac{1}{(m+1)(a\,d-b\,c)(a\,f-b\,e)}\,\cdot | |||
</math><blockquote><math> | |||
\int ((m+1) (A (a\,d\,f-b(c\,f+d\,e))+B\,b\,c\,e)-(A\,b-a\,B) (d\,e(n+1)+c\,f(p+1))-d\,f(m+n+p+3) (A\,b-a\,B)x)(a+b\,x)^{m+1} (c+d\,x)^n(e+f\,x)^p dx | |||
</math></blockquote> | |||
== Integrands of the form ''x''<sup>''m''</sup> (''A'' + ''B x''<sup>''n''</sup>) (''a'' + ''b x''<sup>''n''</sup>)<sup>''p''</sup> (''c'' + ''d x''<sup>''n''</sup>)<sup>''q''</sup> == | |||
* 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>\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^q</math> and <math>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. | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
-\frac{(A\,b-a\,B) x^{m+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^q}{a\,b\,n (p+1)}\,+\, | |||
\frac{1}{a\,b\,n (p+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^m\left(c (A\,b\,n (p+1)+(A\,b-a\,B) (m+1))+d (A\,b\,n (p+1)+(A\,b-a\,B) (m+n\,q+1)) x^n\right)\left(a+b\,x^n\right)^{p+1}\left(c+d\,x^n\right)^{q-1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
\frac{B\,x^{m+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^q}{b (m+n (p+q+1)+1)}\,+\, | |||
\frac{1}{b (m+n (p+q+1)+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^m\left(c ((A\,b-a\,B) (1+m)+A\,b\,n (1+p+q))+(d(A\,b-a\,B) (1+m)+B\,n\,q(b\,c-a\,d)+A\,b\,d\,n (1+p+q))\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^{q-1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
-\frac{(A\,b-a\,B) x^{m+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^{q+1}}{a\,n (b\,c-a\,d) (p+1)}\,+\, | |||
\frac{1}{a\,n(b\,c-a\,d)(p+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^m\left(c(A\,b-a\,B)(m+1)+A\,n (b\,c-a\,d)(p+1)+d(A\,b-a\,B) (m+n (p+q+2)+1) x^n\right)\left(a+b\,x^n\right)^{p+1}\left(c+d\,x^n\right)^qdx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
\frac{B\,x^{m-n+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^{q+1}}{b\,d (m+n (p+q+1)+1)}\,-\, | |||
\frac{1}{b\,d (m+n (p+q+1)+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m-n}\left(a\,B\,c (m-n+1)+(a\,B\,d (m+n\,q+1)-b (-B\,c (m+n\,p+1)+A\,d (m+n (p+q+1)+1))) x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
\frac{A\,x^{m+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^{q+1}}{a\,c (m+1)}\,+\, | |||
\frac{1}{a\,c (m+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m+n}\left(a\,B\,c (m+1)-A (b\,c+a\,d) (m+n+1)-A\,n (b\,c\,p+a\,d\,q)-A\,b\,d (m+n (p+q+2)+1) x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
\frac{A\,x^{m+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^q}{a (m+1)}\,-\, | |||
\frac{1}{a (m+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m+n}\left(c(A\,b-a\,B)(m+1)+A\,n (b\,c (p+1)+a\,d\,q)+d ((A\,b-a\,B) (m+1)+A\,b\,n (p+q+1)) x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^{q-1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m\left(A+B\,x^n\right)\left(a+b\,x^n\right)^p\left(c+d\,x^n\right)^qdx= | |||
\frac{(A\,b-a\,B) x^{m-n+1} \left(a+b\,x^n\right)^{p+1} \left(c+d\,x^n\right)^{q+1}}{b\,n (b\,c-a\,d) (p+1)}\,-\, | |||
\frac{1}{b\,n(b\,c-a\,d)(p+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m-n}\left(c(A\,b-a\,B)(m-n+1)+(d(A\,b-a\,B)(m+n\,q+1)-b\,n(B\,c-A\,d)(p+1)) x^n\right)\left(a+b\,x^n\right)^{p+1}\left(c+d\,x^n\right)^qdx | |||
</math></blockquote> | |||
== Integrands of the form (''d'' + ''e x'')<sup>''m''</sup> (''a'' + ''b x'' + ''c x''<sup>2</sup>)<sup>''p''</sup> when ''b''<sup>2</sup> − 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>\left(a+b\,x+c\,x^2\right)^p</math> when <math>b^2-4\,a\,c=0</math> by setting ''m'' to 0. | |||
:<math> | |||
\int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^{m+1} \left(a+b\,x+c\,x^2\right)^p}{e(m+1)}\,-\, | |||
\frac{p (d+e\,x)^{m+2}(b+2 c\,x) \left(a+b\,x+c\,x^2\right)^{p-1}}{e^2(m+1)(m+2 p+1)}\,+\, | |||
\frac{p(2 p-1)(2 c\,d-b\,e)}{e^2(m+1)(m+2 p+1)} \int (d+e\,x)^{m+1}\left(a+b\,x+c\,x^2\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^{m+1} \left(a+b\,x+c\,x^2\right)^p}{e(m+1)}\,-\, | |||
\frac{p (d+e\,x)^{m+2}(b+2\,c\,x)\left(a+b\,x+c\,x^2\right)^{p-1}}{e^2(m+1)(m+2)}\,+\, | |||
\frac{2\,c\,p\,(2\,p-1)}{e^2(m+1)(m+2)} \int (d+e\,x)^{m+2} \left(a+b\,x+c\,x^2\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m\left(a+b\,x+c\,x^2\right)^pdx= | |||
-\frac{e(m+2 p+2)(d+e\,x)^m \left(a+b\,x+c\,x^2\right)^{p+1}}{(p+1)(2p+1)(2 c\,d-b\,e)}\,+\, | |||
\frac{(d+e\,x)^{m+1}(b+2 c\,x) \left(a+b\,x+c\,x^2\right)^p}{(2p+1)(2 c\,d-b\,e)}\,+\, | |||
\frac{e^2m(m+2 p+2)}{(p+1)(2p+1)(2 c\,d-b\,e)} \int (d+e\,x)^{m-1} \left(a+b\,x+c\,x^2\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^pdx= | |||
-\frac{e\,m(d+e\,x)^{m-1} \left(a+b\,x+c\,x^2\right)^{p+1}}{2c (p+1) (2p+1)}\,+\, | |||
\frac{(d+e\,x)^m(b+2 c\,x)\left(a+b\,x+c\,x^2\right)^p}{2c (2p+1)}\,+\, | |||
\frac{e^2m(m-1)}{2c (p+1) (2p+1)} \int (d+e\,x)^{m-2} \left(a+b\,x+c\,x^2\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^{m+1} \left(a+b\,x+c\,x^2\right)^p}{e(m+2p+1)}\,-\, | |||
\frac{p(2 c\,d-b\,e)(d+e\,x)^{m+1}(b+2 c\,x)\left(a+b\,x+c\,x^2\right)^{p-1}}{2c\,e^2(m+2 p)(m+2p+1)}\,+\, | |||
\frac{p (2 p-1)(2 c\,d-b\,e)^2}{2c\,e^2(m+2 p)(m+2p+1)} \int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^pdx= | |||
-\frac{2c\,e(m+2p+2)(d+e\,x)^{m+1} \left(a+b\,x+c\,x^2\right)^{p+1}}{(p+1) (2 p+1)(2 c\,d-b\,e)^2}\,+\, | |||
\frac{(d+e\,x)^{m+1}(b+2 c\,x)\left(a+b\,x+c\,x^2\right)^p}{(2 p+1)(2 c\,d-b\,e)}\,+\, | |||
\frac{2c\,e^2(m+2p+2)(m+2 p+3)}{(p+1) (2 p+1)(2 c\,d-b\,e)^2} \int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^m (b+2 c\,x)\left(a+b\,x+c\,x^2\right)^p}{2c (m+2p+1)}\,+\, | |||
\frac{m(2 c\,d-b\,e)}{2c (m+2p+1)} \int (d+e\,x)^{m-1}\left(a+b\,x+c\,x^2\right)^pdx | |||
</math> | |||
:<math> | |||
\int (d+e\,x)^m\left(a+b\,x+c\,x^2\right)^pdx= | |||
-\frac{(d+e\,x)^{m+1} (b+2 c\,x)\left(a+b\,x+c\,x^2\right)^p}{(m+1)(2 c\,d-b\,e)}\,+\, | |||
\frac{2c (m+2p+2)}{(m+1)(2 c\,d-b\,e)} \int (d+e\,x)^{m+1} \left(a+b\,x+c\,x^2\right)^pdx | |||
</math> | |||
== Integrands of the form (''d'' + ''e x'')<sup>''m''</sup> (''A'' + ''B x'') (''a'' + ''b x'' + ''c x''<sup>2</sup>)<sup>''p''</sup> == | |||
* 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>\left(a+b\,x+c\,x^2\right)^p</math> and <math>(d+e\,x)^m \left(a+b\,x+c\,x^2\right)^p</math> by setting ''m'' and/or ''B'' to 0. | |||
:<math> | |||
\int (d+e\,x)^m (A+B\,x) \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^{m+1} (A\,e (m+2 p+2)-B\,d (2 p+1)+e\,B (m+1) x) \left(a+b\,x+c\,x^2\right)^p}{e^2(m+1) (m+2 p+2)}\,+\, | |||
\frac{1}{e^2(m+1) (m+2 p+2)}p\,\cdot | |||
</math><blockquote><math> | |||
\int (d+e\,x)^{m+1} (B (b\,d+2 a\,e+2 a\,e\,m+2 b\,d\,p)-A\,b\,e (m+2 p+2)+(B (2 c\,d+b\,e+b\,e m+4 c\,d\,p)-2 A\,c\,e (m+2 p+2))x)\left(a+b\,x+c\,x^2\right)^{p-1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int (d+e\,x)^m (A+B\,x) \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^m (A\,b-2 a\,B-(b\,B-2 A\,c) x)\left(a+b\,x+c\,x^2\right)^{p+1}}{(p+1)\left(b^2-4 a\,c\right) }\,+\, | |||
\frac{1}{(p+1)\left(b^2-4 a\,c\right) }\,\cdot | |||
</math><blockquote><math> | |||
\int (d+e\,x)^{m-1}(B (2 a\,e\,m+b\,d (2 p+3))-A (b\,e\,m+2 c\,d (2 p+3))+e(b\,B-2 A\,c) (m+2 p+3) x)\left(a+b\,x+c\,x^2\right)^{p+1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int (d+e\,x)^m (A+B\,x) \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^{m+1} (A\,c\,e (m+2 p+2)-B (c\,d+2 c\,d\,p-b\,e\,p)+B\,c\,e(m+2 p+1) x)\left(a+b\,x+c\,x^2\right)^p}{c\,e^2(m+2 p+1) (m+2 p+2)}\,-\, | |||
\frac{p}{c\,e^2(m+2 p+1) (m+2 p+2)}\,\cdot | |||
</math><blockquote><math> | |||
\int (d+e\,x)^m (A\,c\,e (b\,d-2 a\,e) (m+2 p+2)+B (a\,e (b\,e-2 c\,d\,m+b\,e\,m)+b\,d (b\,e\,p-c\,d-2 c\,d\,p))+ | |||
</math><blockquote><math> | |||
\left(A\,c\,e (2 c\,d-b\,e) (m+2 p+2)-B \left(-b^2 e^2 (m+p+1)+2 c^2 d^2 (1+2 p)+c\,e (b\,d (m-2 p)+2 a\,e (m+2 p+1))\right)\right) x)\left(a+b\,x+c\,x^2\right)^{p-1}dx | |||
</math></blockquote></blockquote> | |||
:<math> | |||
\int (d+e\,x)^m (A+B\,x) \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{(d+e\,x)^{m+1} \left(A \left(b\,c\,d-b^2 e+2 a\,c\,e\right)-a\,B (2 c\,d-b\,e)+c (A (2 c\,d-b\,e)-B (b\,d-2 a\,e)) x\right)\left(a+b\,x+c\,x^2\right)^{p+1}}{(p+1)\left(b^2-4 a\,c\right) \left(c\,d^2-b\,d\,e+a\,e^2\right)}\,+\, | |||
</math><blockquote><math> | |||
\frac{1}{(p+1)\left(b^2-4 a\,c\right) \left(c\,d^2-b\,d\,e+a\,e^2\right)}\,\cdot | |||
</math><blockquote><math> | |||
\int (d+e\,x)^m (A \left(b\,c\,d\,e (2 p-m+2)+b^2 e^2 (m+p+2)-2 c^2 d^2 (3+2 p)-2 a\,c\,e^2 (m+2 p+3)\right)- | |||
</math><blockquote><math> | |||
B (a\,e (b\,e-2 c\,d m+b\,e\,m)+b\,d (-3 c\,d+b\,e-2 c\,d\,p+b\,e\,p))+c\,e(B (b\,d-2 a\,e)-A (2 c\,d-b\,e)) (m+2 p+4) x)\left(a+b\,x+c\,x^2\right)^{p+1}dx | |||
</math></blockquote></blockquote></blockquote> | |||
:<math> | |||
\int (d+e\,x)^m (A+B\,x) \left(a+b\,x+c\,x^2\right)^pdx= | |||
\frac{B(d+e\,x)^m\left(a+b\,x+c\,x^2\right)^{p+1}}{c(m+2 p+2)}\,+\, | |||
\frac{1}{c(m+2 p+2)}\,\cdot | |||
</math><blockquote><math> | |||
\int (d+e\,x)^{m-1} (m(A\,c\,d-a\,B\,e)-d(b\,B-2 A\,c)(p+1) +((B\,c\,d-b\,B\,e+A\,c\,e) m-e(b\,B-2 A\,c)(p+1))x) \left(a+b\,x+c\,x^2\right)^pdx | |||
</math></blockquote> | |||
:<math> | |||
\int (d+e\,x)^m (A+B\,x) \left(a+b\,x+c\,x^2\right)^pdx= | |||
-\frac{(B\,d-A\,e) (d+e\,x)^{m+1} \left(a+b\,x+c\,x^2\right)^{p+1}}{(m+1)\left(c\,d^2-b\,d\,e+a\,e^2\right)}\,+\, | |||
\frac{1}{(m+1)\left(c\,d^2-b\,d\,e+a\,e^2\right)}\,\cdot | |||
</math><blockquote><math> | |||
\int (d+e\,x)^{m+1} ((A\,c\,d-A\,b\,e+a\,B\,e) (m+1)+b (B\,d-A\,e) (p+1)+c (B\,d-A\,e) (m+2 p+3) x)\left(a+b\,x+c\,x^2\right)^pdx | |||
</math></blockquote> | |||
== Integrands of the form ''x''<sup>''m''</sup> (''a'' + ''b x''<sup>''n''</sup> + ''c x''<sup>2''n''</sup>)<sup>''p''</sup> when ''b''<sup>2</sup> − 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>\left(a+b\,x^n+c\,x^{2 n}\right)^p</math> when <math>b^2-4\,a\,c=0</math> by setting ''m'' to 0. | |||
:<math> | |||
\int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
\frac{ x^{m+1}\left(a+b\,x^n+c\,x^{2 n}\right)^p}{m+2 n\,p+1}\,+\, | |||
\frac{n\,p\,x^{m+1} \left(2 a+b\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}}{(m+1)(m+2 n\,p+1)}\,-\, | |||
\frac{b\,n^2 p (2 p-1)}{(m+1)(m+2 n\,p+1)} \int x^{m+n} \left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
\frac{(m+n(2 p-1)+1) x^{m+1}\left(a+b\,x^n+c\,x^{2 n}\right)^p}{(m+1)(m+n+1)}\,+\, | |||
\frac{n\,p\,x^{m+1} \left(2 a+b\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}}{(m+1)(m+n+1)}\,+\, | |||
\frac{2 c\,p\,n^2(2 p-1)}{(m+1)(m+n+1)} \int x^{m+2n} \left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
\frac{(m+n(2 p+1)+1) x^{m-n+1}\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{b\,n^2 (p+1) (2p+1)}\,-\, | |||
\frac{x^{m+1} \left(b+2 c\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^p}{b\,n (2p+1)}\,-\, | |||
\frac{(m-n+1)(m+n(2 p+1)+1)}{b\,n^2 (p+1) (2p+1)} \int x^{m-n} \left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
-\frac{(m-3 n-2 n\,p+1) x^{m-2n+1}\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{2 c\,n^2(p+1)(2p+1)}\,-\, | |||
\frac{ x^{m-2n+1} \left(2 a+b\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^p}{2 c\,n(2p+1)}\,+\, | |||
\frac{(m-n+1)(m-2n+1)}{2 c\,n^2(p+1)(2p+1)} \int x^{m-2n} \left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
\frac{x^{m+1}\left(a+b\,x^n+c\,x^{2 n}\right)^p}{m+2 n\,p+1}\,+\, | |||
\frac{n\,p\,x^{m+1} \left(2 a+b\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}}{(m+2 n\,p+1) (m+n(2 p-1)+1)}\,+\, | |||
\frac{2 a\,n^2 p (2 p-1)}{(m+2 n\,p+1) (m+n(2 p-1)+1)} \int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}dx | |||
</math> | |||
:<math> | |||
\int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
-\frac{(m+n+2 n\,p+1) x^{m+1}\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{2 a\,n^2 (p+1) (2p+1)}\,-\, | |||
\frac{x^{m+1} \left(2 a+b\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^p}{2 a\,n(2p+1)}\,+\, | |||
\frac{(m+n(2 p+1)+1)(m+2 n (p+1)+1)}{2 a\,n^2 (p+1) (2p+1)} \int x^m \left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}dx | |||
</math> | |||
:<math> | |||
\int x^m\left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
\frac{x^{m-n+1} \left(b+2c\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^p}{2c (m+2n\,p+1)}\,-\, | |||
\frac{b (m-n+1)}{2c (m+2n\,p+1)} \int x^{m-n} \left(a+b\,x^n+c\,x^{2 n}\right)^p dx | |||
</math> | |||
:<math> | |||
\int x^m\left(a+b\,x^n+c\,x^{2 n}\right)^p dx= | |||
\frac{x^{m+1} \left(b+2c\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^p}{b (m+1)}\,-\, | |||
\frac{2c (m+n(2 p+1)+1)}{b (m+1)} \int x^{m+n} \left(a+b\,x^n+c\,x^{2 n}\right)^p dx | |||
</math> | |||
== Integrands of the form ''x''<sup>''m''</sup> (''A'' + ''B x''<sup>''n''</sup>) (''a'' + ''b x''<sup>''n''</sup> + ''c x''<sup>2''n''</sup>)<sup>''p''</sup> == | |||
* 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>\left(a+b\,x^n+c\,x^{2 n}\right)^p</math> and <math>x^m \left(a+b\,x^n+c\,x^{2 n}\right)^p</math> by setting ''m'' and/or ''B'' to 0. | |||
:<math> | |||
\int x^m \left(A+B\,x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx= | |||
\frac{x^{m+1} \left(A (m+n (2 p+1)+1)+B (m+1) x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^p}{(m+1) (m+n (2 p+1)+1)}\,+\, | |||
\frac{n\,p}{(m+1) (m+n (2 p+1)+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m+n} \left(2 a\,B (m+1)-A\,b (m+n (2 p+1)+1)+(b\,B (m+1)-2\,A\,c (m+n (2 p+1)+1)) x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m \left(A+B\,x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx= | |||
\frac{x^{m-n+1} \left(A\,b-2 a\,B-(b\,B-2 A\,c) x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{n(p+1) \left(b^2-4 a\,c\right)}\,+\, | |||
\frac{1}{n(p+1) \left(b^2-4 a\,c\right)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m-n}\left((m-n+1)(2 a\,B-A\,b)+(m+2n (p+1)+1) (b\,B-2 A\,c) x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m \left(A+B\,x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx= | |||
\frac{x^{m+1} \left(b\,B\,n\,p+A\,c (m+n (2 p+1)+1)+B\,c (m+2 n\,p+1) x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^p}{c (m+2 n\,p+1) (m+n (2 p+1)+1)}\,+\, | |||
\frac{n\,p}{c (m+2 n\,p+1) (m+n (2 p+1)+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^m \left(2 a\,A\,c (m+n (2 p+1)+1)-a\,b\,B (m+1)+\left(2 a\,B\,c (m+2 n\,p+1)+A\,b\,c (m+n (2 p+1)+1)-b^2 B (m+n\,p+1)\right) x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p-1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m \left(A+B\,x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx= | |||
-\frac{x^{m+1} \left(A\,b^2-a\,b\,B-2 a\,A\,c+(A\,b-2 a\,B) c\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{a\,n(p+1) \left(b^2-4 a\,c\right)}\,+\, | |||
\frac{1}{a\,n(p+1) \left(b^2-4 a\,c\right)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^m \left((m+n (p+1)+1) A\,b^2-a\,b\,B(m+1)-2(m+2n (p+1)+1)a\,A\,c+(m+n (2p+3)+1)(A\,b-2 a\,B) c\,x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}dx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m \left(A+B\,x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx= | |||
\frac{B\,x^{m-n+1}\left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{c (m+n (2 p+1)+1)}\,-\, | |||
\frac{1}{c (m+n (2 p+1)+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m-n} \left(a\,B (m-n+1)+(b\,B (m+n\,p+1)-A\,c (m+n (2 p+1)+1)) x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx | |||
</math></blockquote> | |||
:<math> | |||
\int x^m \left(A+B\,x^n\right) \left(a+b\,x^n+c\,x^{2 n}\right)^pdx= | |||
\frac{A\,x^{m+1} \left(a+b\,x^n+c\,x^{2 n}\right)^{p+1}}{a(m+1)}\,+\, | |||
\frac{1}{a(m+1)}\,\cdot | |||
</math><blockquote><math> | |||
\int x^{m+n} \left(a\,B (m+1)-A\,b (m+n (p+1)+1)-A\,c (m+2 n(p+1)+1) x^n\right)\left(a+b\,x^n+c\,x^{2 n}\right)^pdx | |||
</math></blockquote> | |||
== References == | |||
{{reflist}} | |||
{{Lists of integrals}} | |||
[[Category:Integrals|Rational functions]] | |||
[[Category:Mathematics-related lists|Integrals of rational functions]] |
Revision as of 16:35, 26 January 2014
The following is a list of integrals (antiderivative functions) of rational functions. For other types of functions, see lists of integrals.
Miscellaneous integrands
Any rational function can be integrated using partial fractions in integration, by decomposing the rational function into a sum of functions of the form:
Integrands of the form xm(a x + b)n
-
- More generally,[1]
- (Cavalieri's quadrature formula)
Integrands of the form xm / (a x2 + b x + c)n
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 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 and 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 when 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 and 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 when 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 and by setting m and/or B to 0.
References
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- ↑ "Reader Survey: log|x| + C", Tom Leinster, The n-category Café, March 19, 2012