Other Bases: Use the Solution Space Theorem to show that the sets given in Problems 1 and 2 are each a basis for the DE?
1. y' - 4y = 0; {e2t, e-2t}, {cosh 2t, sinh 2t}, {e2t, cosh 2t}
2. y" = 0; {1, t}, {t + 1, t - 1}, {2t, 3t - 1}