Sr Examen

Integral de cos(x*t)*cos(y*t) dt

Límites de integración:

interior superior
v

Gráfico:

interior superior

Definida a trozos:

Solución

Ha introducido [src]
  t                     
  /                     
 |                      
 |  cos(x*t)*cos(y*t) dt
 |                      
/                       
0                       
$$\int\limits_{0}^{t} \cos{\left(t x \right)} \cos{\left(t y \right)}\, dt$$
Integral(cos(x*t)*cos(y*t), (t, 0, t))
Respuesta (Indefinida) [src]
                              /                    /t*x   t*y\                              /                    /t*x   t*y\                          
                              |               2*tan|--- + ---|                              |               2*tan|--- - ---|                          
                              |                    \ 2     2 /                              |                    \ 2     2 /                          
                              |---------------------------------------------  for x != -y   |---------------------------------------------  for x != y
                              <             2/t*x   t*y\        2/t*x   t*y\                <             2/t*x   t*y\        2/t*x   t*y\            
                              |x + y + x*tan |--- + ---| + y*tan |--- + ---|                |x - y + x*tan |--- - ---| - y*tan |--- - ---|            
                              |              \ 2     2 /         \ 2     2 /                |              \ 2     2 /         \ 2     2 /            
  /                           |                                                             |                                                         
 |                            \                      t                         otherwise    \                      t                        otherwise 
 | cos(x*t)*cos(y*t) dt = C + ----------------------------------------------------------- + ----------------------------------------------------------
 |                                                         2                                                            2                             
/                                                                                                                                                     
$$\int \cos{\left(t x \right)} \cos{\left(t y \right)}\, dt = C + \frac{\begin{cases} \frac{2 \tan{\left(\frac{t x}{2} - \frac{t y}{2} \right)}}{x \tan^{2}{\left(\frac{t x}{2} - \frac{t y}{2} \right)} + x - y \tan^{2}{\left(\frac{t x}{2} - \frac{t y}{2} \right)} - y} & \text{for}\: x \neq y \\t & \text{otherwise} \end{cases}}{2} + \frac{\begin{cases} \frac{2 \tan{\left(\frac{t x}{2} + \frac{t y}{2} \right)}}{x \tan^{2}{\left(\frac{t x}{2} + \frac{t y}{2} \right)} + x + y \tan^{2}{\left(\frac{t x}{2} + \frac{t y}{2} \right)} + y} & \text{for}\: x \neq - y \\t & \text{otherwise} \end{cases}}{2}$$
Respuesta [src]
/                      t                                                      for Or(And(x = 0, y = 0), And(x = 0, x = y, y = 0), And(x = 0, x = -y, y = 0), And(x = 0, x = -y, x = y, y = 0))                               
|                                                                                                                                                                                                                            
|     2             2                                                                                                                                                                                                        
|t*cos (t*y)   t*sin (t*y)   cos(t*y)*sin(t*y)                                                                                                                                                                               
|----------- + ----------- + -----------------  for Or(And(x = 0, x = -y), And(x = 0, x = y), And(x = -y, x = y), And(x = y, y = 0), And(x = -y, y = 0), And(x = 0, x = -y, x = y), And(x = -y, x = y, y = 0), x = -y, x = y)
<     2             2               2*y                                                                                                                                                                                      
|                                                                                                                                                                                                                            
|  x*cos(t*y)*sin(t*x)   y*cos(t*x)*sin(t*y)                                                                                                                                                                                 
|  ------------------- - -------------------                                                                                      otherwise                                                                                  
|         2    2                2    2                                                                                                                                                                                       
\        x  - y                x  - y                                                                                                                                                                                        
$$\begin{cases} t & \text{for}\: \left(x = 0 \wedge y = 0\right) \vee \left(x = 0 \wedge x = y \wedge y = 0\right) \vee \left(x = 0 \wedge x = - y \wedge y = 0\right) \vee \left(x = 0 \wedge x = - y \wedge x = y \wedge y = 0\right) \\\frac{t \sin^{2}{\left(t y \right)}}{2} + \frac{t \cos^{2}{\left(t y \right)}}{2} + \frac{\sin{\left(t y \right)} \cos{\left(t y \right)}}{2 y} & \text{for}\: \left(x = 0 \wedge x = - y\right) \vee \left(x = 0 \wedge x = y\right) \vee \left(x = - y \wedge x = y\right) \vee \left(x = y \wedge y = 0\right) \vee \left(x = - y \wedge y = 0\right) \vee \left(x = 0 \wedge x = - y \wedge x = y\right) \vee \left(x = - y \wedge x = y \wedge y = 0\right) \vee x = - y \vee x = y \\\frac{x \sin{\left(t x \right)} \cos{\left(t y \right)}}{x^{2} - y^{2}} - \frac{y \sin{\left(t y \right)} \cos{\left(t x \right)}}{x^{2} - y^{2}} & \text{otherwise} \end{cases}$$
=
=
/                      t                                                      for Or(And(x = 0, y = 0), And(x = 0, x = y, y = 0), And(x = 0, x = -y, y = 0), And(x = 0, x = -y, x = y, y = 0))                               
|                                                                                                                                                                                                                            
|     2             2                                                                                                                                                                                                        
|t*cos (t*y)   t*sin (t*y)   cos(t*y)*sin(t*y)                                                                                                                                                                               
|----------- + ----------- + -----------------  for Or(And(x = 0, x = -y), And(x = 0, x = y), And(x = -y, x = y), And(x = y, y = 0), And(x = -y, y = 0), And(x = 0, x = -y, x = y), And(x = -y, x = y, y = 0), x = -y, x = y)
<     2             2               2*y                                                                                                                                                                                      
|                                                                                                                                                                                                                            
|  x*cos(t*y)*sin(t*x)   y*cos(t*x)*sin(t*y)                                                                                                                                                                                 
|  ------------------- - -------------------                                                                                      otherwise                                                                                  
|         2    2                2    2                                                                                                                                                                                       
\        x  - y                x  - y                                                                                                                                                                                        
$$\begin{cases} t & \text{for}\: \left(x = 0 \wedge y = 0\right) \vee \left(x = 0 \wedge x = y \wedge y = 0\right) \vee \left(x = 0 \wedge x = - y \wedge y = 0\right) \vee \left(x = 0 \wedge x = - y \wedge x = y \wedge y = 0\right) \\\frac{t \sin^{2}{\left(t y \right)}}{2} + \frac{t \cos^{2}{\left(t y \right)}}{2} + \frac{\sin{\left(t y \right)} \cos{\left(t y \right)}}{2 y} & \text{for}\: \left(x = 0 \wedge x = - y\right) \vee \left(x = 0 \wedge x = y\right) \vee \left(x = - y \wedge x = y\right) \vee \left(x = y \wedge y = 0\right) \vee \left(x = - y \wedge y = 0\right) \vee \left(x = 0 \wedge x = - y \wedge x = y\right) \vee \left(x = - y \wedge x = y \wedge y = 0\right) \vee x = - y \vee x = y \\\frac{x \sin{\left(t x \right)} \cos{\left(t y \right)}}{x^{2} - y^{2}} - \frac{y \sin{\left(t y \right)} \cos{\left(t x \right)}}{x^{2} - y^{2}} & \text{otherwise} \end{cases}$$
Piecewise((t, ((x = 0)∧(y = 0))∨((x = 0)∧(x = y)∧(y = 0))∨((x = 0)∧(y = 0)∧(x = -y))∨((x = 0)∧(x = y)∧(y = 0)∧(x = -y))), (t*cos(t*y)^2/2 + t*sin(t*y)^2/2 + cos(t*y)*sin(t*y)/(2*y), (x = y)∨(x = -y)∨((x = 0)∧(x = y))∨((x = y)∧(y = 0))∨((x = 0)∧(x = -y))∨((x = y)∧(x = -y))∨((y = 0)∧(x = -y))∨((x = 0)∧(x = y)∧(x = -y))∨((x = y)∧(y = 0)∧(x = -y))), (x*cos(t*y)*sin(t*x)/(x^2 - y^2) - y*cos(t*x)*sin(t*y)/(x^2 - y^2), True))

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