Question

Determine order and degree (if defined) of differential equation $\frac{d^2y}{dx^2}=\cos 3x+\sin3x$

Answer 1

$\frac{d^2y}{dx^2}=\cos 3x+\sin3x$
$\Rightarrow\frac{d^2y}{dx^2}-\cos3x-\sin3x=0$
The highest order derivative present in the differential equation is $\frac{d^2y}{dx^2}.$
Therefore, its order is two.
It is a polynomial equation in $\frac{d^2y}{dx^2}$ and the power raised to $\frac{d^2y}{dx^2}$ is 1.

Hence, its degree is one.