Question
Obtain the differential equation from the equation y = ex (a cos 2x + b sin 2x). where a and b are arbitrary constants.
Solution
The given equation is
y = ex (a cos 2x + b sin 2x) ... (1)
Differentiating both sides w.r.t x, we get,
...(2)
Again differentiating w.r.t x,
or 
or 
or 
which is required differential equation.
