Final answer:
The general solution to the ODE with the given roots and their multiplicities is y(t) = C1 * e^(-1 * t) + C2 * t^(2-1) * e^(-2 * t).
Step-by-step explanation:
The general solution to the ODE with the given roots and their multiplicities can be found using the formula:
y(t) = C1 * e^(r1 * t) + C2 * t^(k1-1) * e^(r2 * t)
Substituting the given values:
y(t) = C1 * e^(-1 * t) + C2 * t^(2-1) * e^(-2 * t)
where C1 and C2 are arbitrary constants which can be determined by initial conditions or boundary conditions.