which one of the following differential equation is not linear ?

Options

A. `(d^(2)y)/(dx^(2)) +4y =0`
B. ` x(dy)/(dx) +y = x^(3)`
C. ` (x-y)^(2) (dy)/(dx) =9`
D. ` cos^(2) x (dy)/(dx) +y = tan x`

Answer

A

Explanation

Differential equation given in option (a) is not linear.
because differential coefficient `(dy)/(dx)` has exponent 2.