Sr Examen

Integral de x(pi-x)sinkx dx

Límites de integración:

interior superior
v

Gráfico:

interior superior

Definida a trozos:

Solución

Ha introducido [src]
 pi                       
  /                       
 |                        
 |  x*(pi - x)*sin(k*x) dx
 |                        
/                         
0                         
$$\int\limits_{0}^{\pi} x \left(\pi - x\right) \sin{\left(k x \right)}\, dx$$
Integral((x*(pi - x))*sin(k*x), (x, 0, pi))
Respuesta (Indefinida) [src]
                                  //                  0                     for k = 0\                                                                                                            
                                  ||                                                 |                                                                                                            
                                  || //cos(k*x)   x*sin(k*x)            \            |      /  //            0              for k = 0\                             \                              
                                  || ||-------- + ----------  for k != 0|            |      |  ||                                    |                             |                              
  /                               || ||    2          k                 |            |      |  || //sin(k*x)            \            |     //    0       for k = 0\|      //    0       for k = 0\
 |                                || ||   k                             |            |      |  || ||--------  for k != 0|            |     ||                     ||    2 ||                     |
 | x*(pi - x)*sin(k*x) dx = C + 2*|<-|<                                 |            | + pi*|- |<-|<   k                |            | + x*|<-cos(k*x)            || - x *|<-cos(k*x)            |
 |                                || ||          2                      |            |      |  || ||                    |            |     ||----------  otherwise||      ||----------  otherwise|
/                                 || ||         x                       |            |      |  || \\   x      otherwise /            |     \\    k                /|      \\    k                /
                                  || ||         --            otherwise |            |      |  ||-------------------------  otherwise|                             |                              
                                  || \\         2                       /            |      \  \\            k                       /                             /                              
                                  ||--------------------------------------  otherwise|                                                                                                            
                                  \\                  k                              /                                                                                                            
$$\int x \left(\pi - x\right) \sin{\left(k x \right)}\, dx = C - x^{2} \left(\begin{cases} 0 & \text{for}\: k = 0 \\- \frac{\cos{\left(k x \right)}}{k} & \text{otherwise} \end{cases}\right) + \pi \left(x \left(\begin{cases} 0 & \text{for}\: k = 0 \\- \frac{\cos{\left(k x \right)}}{k} & \text{otherwise} \end{cases}\right) - \begin{cases} 0 & \text{for}\: k = 0 \\- \frac{\begin{cases} \frac{\sin{\left(k x \right)}}{k} & \text{for}\: k \neq 0 \\x & \text{otherwise} \end{cases}}{k} & \text{otherwise} \end{cases}\right) + 2 \left(\begin{cases} 0 & \text{for}\: k = 0 \\- \frac{\begin{cases} \frac{x \sin{\left(k x \right)}}{k} + \frac{\cos{\left(k x \right)}}{k^{2}} & \text{for}\: k \neq 0 \\\frac{x^{2}}{2} & \text{otherwise} \end{cases}}{k} & \text{otherwise} \end{cases}\right)$$
Respuesta [src]
/2    2*cos(pi*k)   pi*sin(pi*k)                                  
|-- - ----------- - ------------  for And(k > -oo, k < oo, k != 0)
| 3         3             2                                       

            
$$\begin{cases} - \frac{\pi \sin{\left(\pi k \right)}}{k^{2}} - \frac{2 \cos{\left(\pi k \right)}}{k^{3}} + \frac{2}{k^{3}} & \text{for}\: k > -\infty \wedge k < \infty \wedge k \neq 0 \\0 & \text{otherwise} \end{cases}$$
=
=
/2    2*cos(pi*k)   pi*sin(pi*k)                                  
|-- - ----------- - ------------  for And(k > -oo, k < oo, k != 0)
| 3         3             2                                       

            
$$\begin{cases} - \frac{\pi \sin{\left(\pi k \right)}}{k^{2}} - \frac{2 \cos{\left(\pi k \right)}}{k^{3}} + \frac{2}{k^{3}} & \text{for}\: k > -\infty \wedge k < \infty \wedge k \neq 0 \\0 & \text{otherwise} \end{cases}$$
Piecewise((2/k^3 - 2*cos(pi*k)/k^3 - pi*sin(pi*k)/k^2, (k > -oo)∧(k < oo)∧(Ne(k, 0))), (0, True))

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