The differential equation is
and initial condition is
.
Rewrite the differential equation as
.
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
.

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

.