Sr Examen

Integral de xdx/cos^2x dx

Límites de integración:

interior superior
v

Gráfico:

interior superior

Definida a trozos:

Solución

Ha introducido [src]
  0           
  /           
 |            
 |     x      
 |  ------- dx
 |     2      
 |  cos (x)   
 |            
/             
pi            
--            
4             
$$\int\limits_{\frac{\pi}{4}}^{0} \frac{x}{\cos^{2}{\left(x \right)}}\, dx$$
Integral(x/cos(x)^2, (x, pi/4, 0))
Respuesta (Indefinida) [src]
  /                    /       2/x\\      /       /x\\      /        /x\\      2/x\    /       /x\\      2/x\    /        /x\\      2/x\    /       2/x\\           /x\ 
 |                  log|1 + tan |-||   log|1 + tan|-||   log|-1 + tan|-||   tan |-|*log|1 + tan|-||   tan |-|*log|-1 + tan|-||   tan |-|*log|1 + tan |-||    2*x*tan|-| 
 |    x                \        \2//      \       \2//      \        \2//       \2/    \       \2//       \2/    \        \2//       \2/    \        \2//           \2/ 
 | ------- dx = C + ---------------- - --------------- - ---------------- + ----------------------- + ------------------------ - ------------------------ - ------------
 |    2                       2/x\               2/x\              2/x\                   2/x\                      2/x\                       2/x\                 2/x\
 | cos (x)            -1 + tan |-|       -1 + tan |-|      -1 + tan |-|           -1 + tan |-|              -1 + tan |-|               -1 + tan |-|         -1 + tan |-|
 |                             \2/                \2/               \2/                    \2/                       \2/                        \2/                  \2/
/                                                                                                                                                                       
$$\int \frac{x}{\cos^{2}{\left(x \right)}}\, dx = C - \frac{2 x \tan{\left(\frac{x}{2} \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1} + \frac{\log{\left(\tan{\left(\frac{x}{2} \right)} - 1 \right)} \tan^{2}{\left(\frac{x}{2} \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1} - \frac{\log{\left(\tan{\left(\frac{x}{2} \right)} - 1 \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1} + \frac{\log{\left(\tan{\left(\frac{x}{2} \right)} + 1 \right)} \tan^{2}{\left(\frac{x}{2} \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1} - \frac{\log{\left(\tan{\left(\frac{x}{2} \right)} + 1 \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1} - \frac{\log{\left(\tan^{2}{\left(\frac{x}{2} \right)} + 1 \right)} \tan^{2}{\left(\frac{x}{2} \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1} + \frac{\log{\left(\tan^{2}{\left(\frac{x}{2} \right)} + 1 \right)}}{\tan^{2}{\left(\frac{x}{2} \right)} - 1}$$
Gráfica
Respuesta [src]
                                                       /                2\               2    /                2\                                        2                                       2           
                 /      ___\          /  ___\          |    /       ___\ |   /       ___\     |    /       ___\ |         /       ___\       /       ___\  /          /      ___\\   /       ___\     /  ___\
       pi*I + log\2 - \/ 2 /       log\\/ 2 /       log\1 + \-1 + \/ 2 / /   \-1 + \/ 2 / *log\1 + \-1 + \/ 2 / /      pi*\-1 + \/ 2 /       \-1 + \/ 2 / *\pi*I + log\2 - \/ 2 //   \-1 + \/ 2 / *log\\/ 2 /
pi*I + --------------------- + ------------------ - ---------------------- + ------------------------------------ + ---------------------- - ------------------------------------- - ------------------------
                          2                     2                      2                               2              /                 2\                              2                                2   
              /       ___\          /       ___\           /       ___\                    /       ___\               |     /       ___\ |                  /       ___\                     /       ___\    
         -1 + \-1 + \/ 2 /     -1 + \-1 + \/ 2 /      -1 + \-1 + \/ 2 /               -1 + \-1 + \/ 2 /             2*\-1 + \-1 + \/ 2 / /             -1 + \-1 + \/ 2 /                -1 + \-1 + \/ 2 /    
$$\frac{\pi \left(-1 + \sqrt{2}\right)}{2 \left(-1 + \left(-1 + \sqrt{2}\right)^{2}\right)} + \frac{\log{\left(\sqrt{2} \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} + \frac{\left(-1 + \sqrt{2}\right)^{2} \log{\left(\left(-1 + \sqrt{2}\right)^{2} + 1 \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} - \frac{\left(-1 + \sqrt{2}\right)^{2} \log{\left(\sqrt{2} \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} - \frac{\log{\left(\left(-1 + \sqrt{2}\right)^{2} + 1 \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} + \frac{\log{\left(2 - \sqrt{2} \right)} + i \pi}{-1 + \left(-1 + \sqrt{2}\right)^{2}} - \frac{\left(-1 + \sqrt{2}\right)^{2} \left(\log{\left(2 - \sqrt{2} \right)} + i \pi\right)}{-1 + \left(-1 + \sqrt{2}\right)^{2}} + i \pi$$
=
=
                                                       /                2\               2    /                2\                                        2                                       2           
                 /      ___\          /  ___\          |    /       ___\ |   /       ___\     |    /       ___\ |         /       ___\       /       ___\  /          /      ___\\   /       ___\     /  ___\
       pi*I + log\2 - \/ 2 /       log\\/ 2 /       log\1 + \-1 + \/ 2 / /   \-1 + \/ 2 / *log\1 + \-1 + \/ 2 / /      pi*\-1 + \/ 2 /       \-1 + \/ 2 / *\pi*I + log\2 - \/ 2 //   \-1 + \/ 2 / *log\\/ 2 /
pi*I + --------------------- + ------------------ - ---------------------- + ------------------------------------ + ---------------------- - ------------------------------------- - ------------------------
                          2                     2                      2                               2              /                 2\                              2                                2   
              /       ___\          /       ___\           /       ___\                    /       ___\               |     /       ___\ |                  /       ___\                     /       ___\    
         -1 + \-1 + \/ 2 /     -1 + \-1 + \/ 2 /      -1 + \-1 + \/ 2 /               -1 + \-1 + \/ 2 /             2*\-1 + \-1 + \/ 2 / /             -1 + \-1 + \/ 2 /                -1 + \-1 + \/ 2 /    
$$\frac{\pi \left(-1 + \sqrt{2}\right)}{2 \left(-1 + \left(-1 + \sqrt{2}\right)^{2}\right)} + \frac{\log{\left(\sqrt{2} \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} + \frac{\left(-1 + \sqrt{2}\right)^{2} \log{\left(\left(-1 + \sqrt{2}\right)^{2} + 1 \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} - \frac{\left(-1 + \sqrt{2}\right)^{2} \log{\left(\sqrt{2} \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} - \frac{\log{\left(\left(-1 + \sqrt{2}\right)^{2} + 1 \right)}}{-1 + \left(-1 + \sqrt{2}\right)^{2}} + \frac{\log{\left(2 - \sqrt{2} \right)} + i \pi}{-1 + \left(-1 + \sqrt{2}\right)^{2}} - \frac{\left(-1 + \sqrt{2}\right)^{2} \left(\log{\left(2 - \sqrt{2} \right)} + i \pi\right)}{-1 + \left(-1 + \sqrt{2}\right)^{2}} + i \pi$$
pi*i + (pi*i + log(2 - sqrt(2)))/(-1 + (-1 + sqrt(2))^2) + log(sqrt(2))/(-1 + (-1 + sqrt(2))^2) - log(1 + (-1 + sqrt(2))^2)/(-1 + (-1 + sqrt(2))^2) + (-1 + sqrt(2))^2*log(1 + (-1 + sqrt(2))^2)/(-1 + (-1 + sqrt(2))^2) + pi*(-1 + sqrt(2))/(2*(-1 + (-1 + sqrt(2))^2)) - (-1 + sqrt(2))^2*(pi*i + log(2 - sqrt(2)))/(-1 + (-1 + sqrt(2))^2) - (-1 + sqrt(2))^2*log(sqrt(2))/(-1 + (-1 + sqrt(2))^2)
Respuesta numérica [src]
-0.438824573117476
-0.438824573117476

    Estos ejemplos se pueden aplicar para introducción de los límites de integración inferior y superior.