Integral de (3x+1)/(x^3+4) dx
Solución
Solución detallada
Vuelva a escribir el integrando:
3 x + 1 x 3 + 4 = 3 x x 3 + 4 + 1 x 3 + 4 \frac{3 x + 1}{x^{3} + 4} = \frac{3 x}{x^{3} + 4} + \frac{1}{x^{3} + 4} x 3 + 4 3 x + 1 = x 3 + 4 3 x + x 3 + 4 1
Integramos término a término:
La integral del producto de una función por una constante es la constante por la integral de esta función:
∫ 3 x x 3 + 4 d x = 3 ∫ x x 3 + 4 d x \int \frac{3 x}{x^{3} + 4}\, dx = 3 \int \frac{x}{x^{3} + 4}\, dx ∫ x 3 + 4 3 x d x = 3 ∫ x 3 + 4 x d x
No puedo encontrar los pasos en la búsqueda de esta integral.
Pero la integral
− 2 3 log ( x + 2 2 3 ) 6 + 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 12 + 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 6 - \frac{\sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)}}{6} + \frac{\sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{12} + \frac{\sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{6} − 6 3 2 l o g ( x + 2 3 2 ) + 12 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 6 3 2 3 atan ( 3 3 2 3 x − 3 3 )
Por lo tanto, el resultado es: − 2 3 log ( x + 2 2 3 ) 2 + 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 4 + 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 2 - \frac{\sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)}}{2} + \frac{\sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{4} + \frac{\sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{2} − 2 3 2 l o g ( x + 2 3 2 ) + 4 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 2 3 2 3 atan ( 3 3 2 3 x − 3 3 )
No puedo encontrar los pasos en la búsqueda de esta integral.
Pero la integral
2 2 3 log ( x + 2 2 3 ) 12 − 2 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 24 + 2 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 12 \frac{2^{\frac{2}{3}} \log{\left(x + 2^{\frac{2}{3}} \right)}}{12} - \frac{2^{\frac{2}{3}} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{24} + \frac{2^{\frac{2}{3}} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{12} 12 2 3 2 l o g ( x + 2 3 2 ) − 24 2 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 12 2 3 2 3 atan ( 3 3 2 3 x − 3 3 )
El resultado es: − 2 3 log ( x + 2 2 3 ) 2 + 2 2 3 log ( x + 2 2 3 ) 12 − 2 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 24 + 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 4 + 2 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 12 + 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 2 - \frac{\sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)}}{2} + \frac{2^{\frac{2}{3}} \log{\left(x + 2^{\frac{2}{3}} \right)}}{12} - \frac{2^{\frac{2}{3}} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{24} + \frac{\sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{4} + \frac{2^{\frac{2}{3}} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{12} + \frac{\sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{2} − 2 3 2 l o g ( x + 2 3 2 ) + 12 2 3 2 l o g ( x + 2 3 2 ) − 24 2 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 4 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 12 2 3 2 3 atan ( 3 3 2 3 x − 3 3 ) + 2 3 2 3 atan ( 3 3 2 3 x − 3 3 )
Ahora simplificar:
2 3 ( − 12 log ( x + 2 2 3 ) + 2 2 3 log ( x + 2 2 3 ) − 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) + 6 log ( x 2 − 2 2 3 x + 2 2 3 ) + 2 2 3 3 atan ( 3 ( 2 3 x − 1 ) 3 ) + 12 3 atan ( 3 ( 2 3 x − 1 ) 3 ) ) 24 \frac{\sqrt[3]{2} \left(- 12 \log{\left(x + 2^{\frac{2}{3}} \right)} + 2 \sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)} - \sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)} + 6 \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)} + 2 \sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt{3} \left(\sqrt[3]{2} x - 1\right)}{3} \right)} + 12 \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt{3} \left(\sqrt[3]{2} x - 1\right)}{3} \right)}\right)}{24} 24 3 2 ( − 12 l o g ( x + 2 3 2 ) + 2 3 2 l o g ( x + 2 3 2 ) − 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 6 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 2 3 2 3 atan ( 3 3 ( 3 2 x − 1 ) ) + 12 3 atan ( 3 3 ( 3 2 x − 1 ) ) )
Añadimos la constante de integración:
2 3 ( − 12 log ( x + 2 2 3 ) + 2 2 3 log ( x + 2 2 3 ) − 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) + 6 log ( x 2 − 2 2 3 x + 2 2 3 ) + 2 2 3 3 atan ( 3 ( 2 3 x − 1 ) 3 ) + 12 3 atan ( 3 ( 2 3 x − 1 ) 3 ) ) 24 + c o n s t a n t \frac{\sqrt[3]{2} \left(- 12 \log{\left(x + 2^{\frac{2}{3}} \right)} + 2 \sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)} - \sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)} + 6 \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)} + 2 \sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt{3} \left(\sqrt[3]{2} x - 1\right)}{3} \right)} + 12 \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt{3} \left(\sqrt[3]{2} x - 1\right)}{3} \right)}\right)}{24}+ \mathrm{constant} 24 3 2 ( − 12 l o g ( x + 2 3 2 ) + 2 3 2 l o g ( x + 2 3 2 ) − 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 6 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 2 3 2 3 atan ( 3 3 ( 3 2 x − 1 ) ) + 12 3 atan ( 3 3 ( 3 2 x − 1 ) ) ) + constant
Respuesta:
2 3 ( − 12 log ( x + 2 2 3 ) + 2 2 3 log ( x + 2 2 3 ) − 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) + 6 log ( x 2 − 2 2 3 x + 2 2 3 ) + 2 2 3 3 atan ( 3 ( 2 3 x − 1 ) 3 ) + 12 3 atan ( 3 ( 2 3 x − 1 ) 3 ) ) 24 + c o n s t a n t \frac{\sqrt[3]{2} \left(- 12 \log{\left(x + 2^{\frac{2}{3}} \right)} + 2 \sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)} - \sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)} + 6 \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)} + 2 \sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt{3} \left(\sqrt[3]{2} x - 1\right)}{3} \right)} + 12 \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt{3} \left(\sqrt[3]{2} x - 1\right)}{3} \right)}\right)}{24}+ \mathrm{constant} 24 3 2 ( − 12 l o g ( x + 2 3 2 ) + 2 3 2 l o g ( x + 2 3 2 ) − 3 2 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 6 l o g ( x 2 − 2 3 2 x + 2 3 2 ) + 2 3 2 3 atan ( 3 3 ( 3 2 x − 1 ) ) + 12 3 atan ( 3 3 ( 3 2 x − 1 ) ) ) + constant
Respuesta (Indefinida)
[src]
/ ___ 3 ___ ___\ / ___ 3 ___ ___\
/ 3 ___ ___ | \/ 3 x*\/ 2 *\/ 3 | 2/3 ___ | \/ 3 x*\/ 2 *\/ 3 |
| 3 ___ / 2/3\ 2/3 / 2 3 ___ 2/3\ 3 ___ / 2 3 ___ 2/3\ 2/3 / 2/3\ \/ 2 *\/ 3 *atan|- ----- + -------------| 2 *\/ 3 *atan|- ----- + -------------|
| 3*x + 1 \/ 2 *log\x + 2 / 2 *log\x + 2*\/ 2 - x*2 / \/ 2 *log\x + 2*\/ 2 - x*2 / 2 *log\x + 2 / \ 3 3 / \ 3 3 /
| ------- dx = C - ------------------- - ------------------------------- + -------------------------------- + ------------------ + ----------------------------------------- + ----------------------------------------
| 3 2 24 4 12 2 12
| x + 4
|
/
∫ 3 x + 1 x 3 + 4 d x = C − 2 3 log ( x + 2 2 3 ) 2 + 2 2 3 log ( x + 2 2 3 ) 12 − 2 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 24 + 2 3 log ( x 2 − 2 2 3 x + 2 2 3 ) 4 + 2 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 12 + 2 3 3 atan ( 2 3 3 x 3 − 3 3 ) 2 \int \frac{3 x + 1}{x^{3} + 4}\, dx = C - \frac{\sqrt[3]{2} \log{\left(x + 2^{\frac{2}{3}} \right)}}{2} + \frac{2^{\frac{2}{3}} \log{\left(x + 2^{\frac{2}{3}} \right)}}{12} - \frac{2^{\frac{2}{3}} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{24} + \frac{\sqrt[3]{2} \log{\left(x^{2} - 2^{\frac{2}{3}} x + 2 \sqrt[3]{2} \right)}}{4} + \frac{2^{\frac{2}{3}} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{12} + \frac{\sqrt[3]{2} \sqrt{3} \operatorname{atan}{\left(\frac{\sqrt[3]{2} \sqrt{3} x}{3} - \frac{\sqrt{3}}{3} \right)}}{2} ∫ x 3 + 4 3 x + 1 d x = C − 2 3 2 log ( x + 2 3 2 ) + 12 2 3 2 log ( x + 2 3 2 ) − 24 2 3 2 log ( x 2 − 2 3 2 x + 2 3 2 ) + 4 3 2 log ( x 2 − 2 3 2 x + 2 3 2 ) + 12 2 3 2 3 atan ( 3 3 2 3 x − 3 3 ) + 2 3 2 3 atan ( 3 3 2 3 x − 3 3 )
Gráfica
2.0000 2.0100 2.0010 2.0020 2.0030 2.0040 2.0050 2.0060 2.0070 2.0080 2.0090 2 -2
/ / -pi*I / pi*I\ pi*I / 5*pi*I\\ \ / / pi*I\ / 5*pi*I\\
| | ------ | ----| ---- | ------|| | | -pi*I | ----| pi*I | ------||
| | 2/3 / 3 ___ pi*I\ 2/3 3 | 3 ___ 3 | 2/3 3 | 3 ___ 3 || | | / 2/3 pi*I\ ------ | 2/3 3 | ---- | 2/3 3 ||
| 3 ___ |2 *log\1 - \/ 2 *e / 2 *e *log\1 - \/ 2 *e / 2 *e *log\1 - \/ 2 *e /| | |3 ___ | 2 *e | 3 ___ 3 | 2 *e | 3 ___ 3 | 2 *e ||
| \/ 2 *|------------------------- - --------------------------------- - ---------------------------------|*Gamma(-1/3)| |\/ 2 *log|1 - ----------| \/ 2 *e *log|1 - ----------| \/ 2 *e *log|1 - ------------||
2/3 | \ 6 6 6 / | | \ 2 / \ 2 / \ 2 /|
2 *|Gamma(1/3)*Gamma(2/3) + ---------------------------------------------------------------------------------------------------------------------| |------------------------- - --------------------------------- - ---------------------------------|*Gamma(1/3)
\ Gamma(2/3) / \ 3 3 3 /
---------------------------------------------------------------------------------------------------------------------------------------------------- + --------------------------------------------------------------------------------------------------------------
12 2*Gamma(4/3)
2 2 3 ( 2 3 ( − 2 2 3 e i π 3 log ( − 2 3 e 5 i π 3 + 1 ) 6 + 2 2 3 log ( 1 − 2 3 e i π ) 6 − 2 2 3 e − i π 3 log ( 1 − 2 3 e i π 3 ) 6 ) Γ ( − 1 3 ) Γ ( 2 3 ) + Γ ( 1 3 ) Γ ( 2 3 ) ) 12 + ( − 2 3 e i π 3 log ( − 2 2 3 e 5 i π 3 2 + 1 ) 3 + 2 3 log ( − 2 2 3 e i π 2 + 1 ) 3 − 2 3 e − i π 3 log ( 1 − 2 2 3 e i π 3 2 ) 3 ) Γ ( 1 3 ) 2 Γ ( 4 3 ) \frac{2^{\frac{2}{3}} \left(\frac{\sqrt[3]{2} \left(- \frac{2^{\frac{2}{3}} e^{\frac{i \pi}{3}} \log{\left(- \sqrt[3]{2} e^{\frac{5 i \pi}{3}} + 1 \right)}}{6} + \frac{2^{\frac{2}{3}} \log{\left(1 - \sqrt[3]{2} e^{i \pi} \right)}}{6} - \frac{2^{\frac{2}{3}} e^{- \frac{i \pi}{3}} \log{\left(1 - \sqrt[3]{2} e^{\frac{i \pi}{3}} \right)}}{6}\right) \Gamma\left(- \frac{1}{3}\right)}{\Gamma\left(\frac{2}{3}\right)} + \Gamma\left(\frac{1}{3}\right) \Gamma\left(\frac{2}{3}\right)\right)}{12} + \frac{\left(- \frac{\sqrt[3]{2} e^{\frac{i \pi}{3}} \log{\left(- \frac{2^{\frac{2}{3}} e^{\frac{5 i \pi}{3}}}{2} + 1 \right)}}{3} + \frac{\sqrt[3]{2} \log{\left(- \frac{2^{\frac{2}{3}} e^{i \pi}}{2} + 1 \right)}}{3} - \frac{\sqrt[3]{2} e^{- \frac{i \pi}{3}} \log{\left(1 - \frac{2^{\frac{2}{3}} e^{\frac{i \pi}{3}}}{2} \right)}}{3}\right) \Gamma\left(\frac{1}{3}\right)}{2 \Gamma\left(\frac{4}{3}\right)} 12 2 3 2 Γ ( 3 2 ) 3 2 − 6 2 3 2 e 3 iπ l o g ( − 3 2 e 3 5 iπ + 1 ) + 6 2 3 2 l o g ( 1 − 3 2 e iπ ) − 6 2 3 2 e − 3 iπ l o g ( 1 − 3 2 e 3 iπ ) Γ ( − 3 1 ) + Γ ( 3 1 ) Γ ( 3 2 ) + 2Γ ( 3 4 ) − 3 3 2 e 3 iπ l o g ( − 2 2 3 2 e 3 5 iπ + 1 ) + 3 3 2 l o g ( − 2 2 3 2 e iπ + 1 ) − 3 3 2 e − 3 iπ l o g ( 1 − 2 2 3 2 e 3 iπ ) Γ ( 3 1 )
=
/ / -pi*I / pi*I\ pi*I / 5*pi*I\\ \ / / pi*I\ / 5*pi*I\\
| | ------ | ----| ---- | ------|| | | -pi*I | ----| pi*I | ------||
| | 2/3 / 3 ___ pi*I\ 2/3 3 | 3 ___ 3 | 2/3 3 | 3 ___ 3 || | | / 2/3 pi*I\ ------ | 2/3 3 | ---- | 2/3 3 ||
| 3 ___ |2 *log\1 - \/ 2 *e / 2 *e *log\1 - \/ 2 *e / 2 *e *log\1 - \/ 2 *e /| | |3 ___ | 2 *e | 3 ___ 3 | 2 *e | 3 ___ 3 | 2 *e ||
| \/ 2 *|------------------------- - --------------------------------- - ---------------------------------|*Gamma(-1/3)| |\/ 2 *log|1 - ----------| \/ 2 *e *log|1 - ----------| \/ 2 *e *log|1 - ------------||
2/3 | \ 6 6 6 / | | \ 2 / \ 2 / \ 2 /|
2 *|Gamma(1/3)*Gamma(2/3) + ---------------------------------------------------------------------------------------------------------------------| |------------------------- - --------------------------------- - ---------------------------------|*Gamma(1/3)
\ Gamma(2/3) / \ 3 3 3 /
---------------------------------------------------------------------------------------------------------------------------------------------------- + --------------------------------------------------------------------------------------------------------------
12 2*Gamma(4/3)
2 2 3 ( 2 3 ( − 2 2 3 e i π 3 log ( − 2 3 e 5 i π 3 + 1 ) 6 + 2 2 3 log ( 1 − 2 3 e i π ) 6 − 2 2 3 e − i π 3 log ( 1 − 2 3 e i π 3 ) 6 ) Γ ( − 1 3 ) Γ ( 2 3 ) + Γ ( 1 3 ) Γ ( 2 3 ) ) 12 + ( − 2 3 e i π 3 log ( − 2 2 3 e 5 i π 3 2 + 1 ) 3 + 2 3 log ( − 2 2 3 e i π 2 + 1 ) 3 − 2 3 e − i π 3 log ( 1 − 2 2 3 e i π 3 2 ) 3 ) Γ ( 1 3 ) 2 Γ ( 4 3 ) \frac{2^{\frac{2}{3}} \left(\frac{\sqrt[3]{2} \left(- \frac{2^{\frac{2}{3}} e^{\frac{i \pi}{3}} \log{\left(- \sqrt[3]{2} e^{\frac{5 i \pi}{3}} + 1 \right)}}{6} + \frac{2^{\frac{2}{3}} \log{\left(1 - \sqrt[3]{2} e^{i \pi} \right)}}{6} - \frac{2^{\frac{2}{3}} e^{- \frac{i \pi}{3}} \log{\left(1 - \sqrt[3]{2} e^{\frac{i \pi}{3}} \right)}}{6}\right) \Gamma\left(- \frac{1}{3}\right)}{\Gamma\left(\frac{2}{3}\right)} + \Gamma\left(\frac{1}{3}\right) \Gamma\left(\frac{2}{3}\right)\right)}{12} + \frac{\left(- \frac{\sqrt[3]{2} e^{\frac{i \pi}{3}} \log{\left(- \frac{2^{\frac{2}{3}} e^{\frac{5 i \pi}{3}}}{2} + 1 \right)}}{3} + \frac{\sqrt[3]{2} \log{\left(- \frac{2^{\frac{2}{3}} e^{i \pi}}{2} + 1 \right)}}{3} - \frac{\sqrt[3]{2} e^{- \frac{i \pi}{3}} \log{\left(1 - \frac{2^{\frac{2}{3}} e^{\frac{i \pi}{3}}}{2} \right)}}{3}\right) \Gamma\left(\frac{1}{3}\right)}{2 \Gamma\left(\frac{4}{3}\right)} 12 2 3 2 Γ ( 3 2 ) 3 2 − 6 2 3 2 e 3 iπ l o g ( − 3 2 e 3 5 iπ + 1 ) + 6 2 3 2 l o g ( 1 − 3 2 e iπ ) − 6 2 3 2 e − 3 iπ l o g ( 1 − 3 2 e 3 iπ ) Γ ( − 3 1 ) + Γ ( 3 1 ) Γ ( 3 2 ) + 2Γ ( 3 4 ) − 3 3 2 e 3 iπ l o g ( − 2 2 3 2 e 3 5 iπ + 1 ) + 3 3 2 l o g ( − 2 2 3 2 e iπ + 1 ) − 3 3 2 e − 3 iπ l o g ( 1 − 2 2 3 2 e 3 iπ ) Γ ( 3 1 )
2^(2/3)*(gamma(1/3)*gamma(2/3) + 2^(1/3)*(2^(2/3)*log(1 - 2^(1/3)*exp_polar(pi*i))/6 - 2^(2/3)*exp(-pi*i/3)*log(1 - 2^(1/3)*exp_polar(pi*i/3))/6 - 2^(2/3)*exp(pi*i/3)*log(1 - 2^(1/3)*exp_polar(5*pi*i/3))/6)*gamma(-1/3)/gamma(2/3))/12 + (2^(1/3)*log(1 - 2^(2/3)*exp_polar(pi*i)/2)/3 - 2^(1/3)*exp(-pi*i/3)*log(1 - 2^(2/3)*exp_polar(pi*i/3)/2)/3 - 2^(1/3)*exp(pi*i/3)*log(1 - 2^(2/3)*exp_polar(5*pi*i/3)/2)/3)*gamma(1/3)/(2*gamma(4/3))
Estos ejemplos se pueden aplicar para introducción de los límites de integración inferior y superior.