Problem 3 (15pts) Use the Laplace transform to find the solution of the problem y"(t) + y(t) = cos(t), y(0) = 1, y(0) = 0. Problem 4 (15pts) Given the system of equations Å Ich x1 = (1 + x2 – 23, x = 2x2 + x3, x's = -23, a) find a fundamental set of solutions of this system, b) Consider the following system x1 = 2tx1 + 22 – 23, x' = 2x2 + t2x3, x'z = -tx3.