The differential equation for which $y=a\cos x+b\sin x$ is a solution is $$(A)\;\frac{d^2y}{dx^2}+y=0 \quad (B)\;\frac{d^2y}{dx^2}-y=0 \quad (C)\;\frac{d^2y}{dx^2}+(a+b)y=0 \quad (D)\;\frac{d^2y}{dx^2}+(a+b)y=0$$

Share

Please log in or register to add a comment.