Which of these is a non-homogeneous linear ODE?
y′+y=xy' + y = xy′+y=x
y′+y=0y' + y = 0y′+y=0
y′′+3y′+2y=0y'' + 3y' + 2y = 0y′′+3y′+2y=0
y=0y = 0y=0