Question

Which of the following differential equations has $y = c_1 e^x + c_2 e^{-x}$ as the general solution?
(A)$\frac{d^2y}{dx^2}+y =0$
(B)$\frac{d^2y}{dx^2}-y =0$
(C)$\frac{d^2y}{dx^2}+1 =0$
(D)$\frac{d^2y}{dx^2}-1 =0$

Answer 1

it is not the sum material for formulas