The differential equation is
and initial condition is
.
The differential equation is a first order linear differential equation.
\Solution of first order linear differential equation
is
.
Compare
with standard form of differential equation.
and
.
First find
.

Apply integration formula
.

.
The solution of differential equation is
.
Substitute
and
in the above equation.

The solution of the differential equation is
.
Initial condition is
.
Substitute
and
in the solution of the differential equation.

Substitute
in the solution of the differential equation.
The solution of the differential equation is 
The solution of the differential equation is
.