Thanks, so for a, the complementary function is y = e^x (A cos E x + B sin E x)
But I'm finding it hard to find the values for A and B to find the general solution.
For example y = e^x (A cos E x + B sin E x) and x=0, y=1
1 = 1(AcosE)
So A = 1/cosE ?
EDIT : it's k = 1+or- E