Solve each of the following initial value problems:
, y(0) = 0
, y(0) = 0
Given and y(0) = 0
This is a first order linear differential equation of the form
Here, P = 2 and Q = e–2xsin x
The integrating factor (I.F) of this differential equation is,
We have
∴ I.F = e2x
Hence, the solution of the differential equation is,
Recall
⇒ ye2x = –cos x + c
⇒ ye2x × e–2x = (–cos x + c) × e–2x
∴ y = (–cos x + c)e–2x
However, when x = 0, we have y = 0
⇒ 0 = (–cos 0 + c)e0
⇒ 0 = (–1 + c) × 1
⇒ 0 = –1 + c
∴ c = 1
By substituting the value of c in the equation for y, we get
y = (–cos x + 1)e–2x
∴ y = (1 – cos x)e–2x
Thus, the solution of the given initial value problem is y = (1 – cos x)e–2x