4. (4 points ) (a ) (7 points ) Find the general solution to y"(t) + 12y'(t) + 36y (t) = 0. (b) (4 points) Write down an appropriate guess for the particular solution (t) for the following equation using the method of undetermined coefficients y "(t) + 3y '(t) - 4y(t) = eat+2. (c) (4 points) Formulate a guess for the particular solution) (t) for the following equation using the method of undetermined coefficients y" (t) + 3y' (t) - 4y (t) = e-at12