l / | | 2 | --*x*cos(x)*sin(n*x) dx | pi | / 0
Integral((((2/pi)*x)*cos(x))*sin(n*x), (x, 0, l))
// / 2 2 \ \ || | x*cos (x) x*sin (x) cos(x)*sin(x)| | || -2*|- --------- + --------- + -------------| | || \ 4 4 4 / | || -------------------------------------------- for n = -1| || pi | || | / || / 2 2 \ | | || | x*cos (x) x*sin (x) cos(x)*sin(x)| | | 2 || 2*|- --------- + --------- + -------------| | | --*x*cos(x)*sin(n*x) dx = C + |< \ 4 4 4 / | | pi || ------------------------------------------- for n = 1 | | || pi | / || | || / 2 2 3 \ | || |cos(x)*sin(n*x) x*sin(x)*sin(n*x) n *cos(x)*sin(n*x) 2*n*cos(n*x)*sin(x) n*x*cos(x)*cos(n*x) x*n *sin(x)*sin(n*x) x*n *cos(x)*cos(n*x)| | ||2*|--------------- + ----------------- + ------------------ - ------------------- + ------------------- - -------------------- - --------------------| | || | 4 2 4 2 4 2 4 2 4 2 4 2 4 2 | | || \ 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n / | ||------------------------------------------------------------------------------------------------------------------------------------------------------ otherwise | \\ pi /
/ / 2 2 \ | | l*sin (l) cos(l)*sin(l) l*cos (l)| | 2*|- --------- - ------------- + ---------| | \ 4 4 4 / | ------------------------------------------- for n = -1 | pi | | / 2 2 \ | | l*cos (l) l*sin (l) cos(l)*sin(l)| | 2*|- --------- + --------- + -------------| < \ 4 4 4 / | ------------------------------------------- for n = 1 | pi | | / 2 2 3 \ | |cos(l)*sin(l*n) l*sin(l)*sin(l*n) n *cos(l)*sin(l*n) 2*n*cos(l*n)*sin(l) l*n*cos(l)*cos(l*n) l*n *sin(l)*sin(l*n) l*n *cos(l)*cos(l*n)| |2*|--------------- + ----------------- + ------------------ - ------------------- + ------------------- - -------------------- - --------------------| | | 4 2 4 2 4 2 4 2 4 2 4 2 4 2 | | \ 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n / |------------------------------------------------------------------------------------------------------------------------------------------------------ otherwise \ pi
=
/ / 2 2 \ | | l*sin (l) cos(l)*sin(l) l*cos (l)| | 2*|- --------- - ------------- + ---------| | \ 4 4 4 / | ------------------------------------------- for n = -1 | pi | | / 2 2 \ | | l*cos (l) l*sin (l) cos(l)*sin(l)| | 2*|- --------- + --------- + -------------| < \ 4 4 4 / | ------------------------------------------- for n = 1 | pi | | / 2 2 3 \ | |cos(l)*sin(l*n) l*sin(l)*sin(l*n) n *cos(l)*sin(l*n) 2*n*cos(l*n)*sin(l) l*n*cos(l)*cos(l*n) l*n *sin(l)*sin(l*n) l*n *cos(l)*cos(l*n)| |2*|--------------- + ----------------- + ------------------ - ------------------- + ------------------- - -------------------- - --------------------| | | 4 2 4 2 4 2 4 2 4 2 4 2 4 2 | | \ 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n 1 + n - 2*n / |------------------------------------------------------------------------------------------------------------------------------------------------------ otherwise \ pi
Piecewise((2*(-l*sin(l)^2/4 - cos(l)*sin(l)/4 + l*cos(l)^2/4)/pi, n = -1), (2*(-l*cos(l)^2/4 + l*sin(l)^2/4 + cos(l)*sin(l)/4)/pi, n = 1), (2*(cos(l)*sin(l*n)/(1 + n^4 - 2*n^2) + l*sin(l)*sin(l*n)/(1 + n^4 - 2*n^2) + n^2*cos(l)*sin(l*n)/(1 + n^4 - 2*n^2) - 2*n*cos(l*n)*sin(l)/(1 + n^4 - 2*n^2) + l*n*cos(l)*cos(l*n)/(1 + n^4 - 2*n^2) - l*n^2*sin(l)*sin(l*n)/(1 + n^4 - 2*n^2) - l*n^3*cos(l)*cos(l*n)/(1 + n^4 - 2*n^2))/pi, True))
Estos ejemplos se pueden aplicar para introducción de los límites de integración inferior y superior.