Problems on Special Form of X in Differential Equation (Type-2):
1. Solve (D2 9)y = cos 4x.
Solution: Given equation is (D2 9)y = cos 4x
A.E is m2 9 = 0
i.e m = ±3i
∴ The general equation is y = C.F P.I
2. Solve (D2 D 1) y = sin2x
Solution: The A.E is m2 m 1 = 0
Multiply and divide by (D 3)
