Integral de x*(x-2)*cos(pi*n*x/2) dx
Solución
Respuesta (Indefinida)
[src]
// 3 \
|| x | // 2 \
|| -- for n = 0| || x |
|| 3 | || -- for n = 0|
|| | || 2 |
/ || // /pi*n*x\ /pi*n*x\ \ | || | // x for n = 0\ // x for n = 0\
| || ||4*sin|------| 2*x*cos|------| | | || // /pi*n*x\ \ | || | || |
| /pi*n*x\ || || \ 2 / \ 2 / | | || ||-2*cos|------| | | 2 || /pi*n*x\ | || /pi*n*x\ |
| x*(x - 2)*cos|------| dx = C - 2*|< ||------------- - --------------- for n != 0| | + 2*|< || \ 2 / pi*n | | + x *|<2*sin|------| | - 2*x*|<2*sin|------| |
| \ 2 / ||2*|< 2 2 pi*n | | ||2*|<-------------- for ---- != 0| | || \ 2 / | || \ 2 / |
| || || pi *n | | || || pi*n 2 | | ||------------- otherwise| ||------------- otherwise|
/ || || | | || || | | \\ pi*n / \\ pi*n /
|| || 0 otherwise | | || \\ 0 otherwise / |
|| \\ / | ||---------------------------------- otherwise|
||------------------------------------------------ otherwise| || pi*n |
|| pi*n | \\ /
\\ /
∫x(x−2)cos(2xπn)dx=C+x2({xπn2sin(2πnx)forn=0otherwise)−2x({xπn2sin(2πnx)forn=0otherwise)+2⎩⎨⎧2x2πn2({−πn2cos(2πnx)0for2πn=0otherwise)forn=0otherwise−2⎩⎨⎧3x3πn2({−πn2xcos(2πnx)+π2n24sin(2πnx)0forn=0otherwise)forn=0otherwise
/ 8 16*sin(pi*n) 8*cos(pi*n)
|------ - ------------ + ----------- for And(n > -oo, n < oo, n != 0)
| 2 2 3 3 2 2
{π2n28cos(πn)+π2n28−π3n316sin(πn)−34forn>−∞∧n<∞∧n=0otherwise
=
/ 8 16*sin(pi*n) 8*cos(pi*n)
|------ - ------------ + ----------- for And(n > -oo, n < oo, n != 0)
| 2 2 3 3 2 2
{π2n28cos(πn)+π2n28−π3n316sin(πn)−34forn>−∞∧n<∞∧n=0otherwise
Piecewise((8/(pi^2*n^2) - 16*sin(pi*n)/(pi^3*n^3) + 8*cos(pi*n)/(pi^2*n^2), (n > -oo)∧(n < oo)∧(Ne(n, 0))), (-4/3, True))
Estos ejemplos se pueden aplicar para introducción de los límites de integración inferior y superior.