Use Theorem 1 to find the general solution to each of the following systems. Then find a specific solution satisfying the given boundary condition.
(a) f′1= -f1 + 5f2, f1(0) = 1
f′1 = f1 + 3f2, f2(0) = -1
(b) f′1 = 2f1 + f2 + 2f3
f′2 = 2f1 + 2f2 - 2f3,
f′3 = 3f1 + f2 + f3
f1(0) = f2(0) = f3(0) =1