微分方程求解 dx⼀dt=x+sint

2025-01-04 03:46:37
推荐回答(2个)
回答1:

解:

回答2:

dx/dt = x+ sint
dx/dt - x = sint
let
xp = Asint +Bcost
xp'= Acost -Bsint
xp' - xp= sint
(A-B)sint +(A+B)cost =sint
A-B =1 (1)
A+B=0 (2)
(2)-(1)
B = -1/2
(1)+(2)
A= 1/2
ie
x = Ce^(t) + (1/2)sint -(1/2)cost