To solve the given differential equation, we need to analyze the characteristic equation associated with it. The characteristic equation will help us determine the behavior of the solutions as \( t \rightarrow \infty \).
- Write the characteristic equation for the given differential equation.
- Solve the characteristic equation to find the roots.
- Analyze the roots to determine the conditions under which the solutions tend to zero or become unbounded as \( t \rightarrow \infty \).
Given the differential equation:
\[
y'' - (2\alpha - 1)y' + \alpha(\alpha - 1)y = 0
\]
we can write the characteristic equation as:
\[
r^2 - (2\alpha - 1)r + \alpha(\alpha - 1) = 0
\]
Solving the characteristic equation, we find the roots:
\[
r = \alpha \quad \text{and} \quad r = \alpha - 1
\]
To determine the behavior of the solutions as \( t \to \infty \), we analyze the real parts of the roots.
For all solutions to tend to zero as \( t \to \infty \), both roots must have negative real parts. Therefore, we need:
\[
\alpha < 0 \quad \text{and} \quad \alpha - 1 < 0
\]
Solving these inequalities, we get:
\[
\alpha < 0
\]
For all (nonzero) solutions to become unbounded as \( t \to \infty \), at least one root must have a positive real part. Therefore, we need:
\[
\alpha > 0 \quad \text{or} \quad \alpha - 1 > 0
\]
Solving these inequalities, we get:
\[
\alpha > 1
\]