Problem: Solve the second-order homogeneous differential equation with initial conditions:
\[
y'' - 3y' + 2y = 0,\quad y(0)=3,\quad y'(0)=1.
\]
Solution: We begin by finding the general solution of the homogeneous equation
\[
y'' - 3y' + 2y = 0.
\]
Assume a solution of the form \(y = e^{rx}\). Then
\[
r^2e^{rx} - 3re^{rx} + 2e^{rx} = 0,
\]
or equivalently, after dividing by \(e^{rx}\) (which is never zero),
\[
r^2 - 3r + 2 = 0.
\]
This factors as
\[
(r-1)(r-2)=0,
\]
so that the characteristic roots are \(r=1\) and \(r=2\). Therefore, the general solution is
\[
y(x)= C_1e^{x}+C_2e^{2x}.
\]
Now we use the initial conditions to find \(C_1\) and \(C_2\).
For \(x=0\):
\[
y(0)= C_1+C_2 = 3.
\]
Differentiating, we have
\[
y'(x)= C_1e^{x}+2C_2e^{2x}.
\]
Thus, at \(x=0\):
\[
y'(0)= C_1+2C_2 = 1.
\]
Subtracting the first equation from the second, we get:
\[
(C_1+2C_2)-(C_1+C_2)= 1-3 \quad \Longrightarrow \quad C_2 = -2.
\]
Then, \(C_1= 3-C_2= 3-(-2)= 5\).
Thus, the solution is
\[
\textcolor{blue}{\boxed{y(x)= 5e^{x}-2e^{2x}.}}
\]