Question

I'm supposed to find a fundamental set of solutions of the system x' = [4, 0; 3, -1]x, and then using the fundamental set to compute the matrix exponential function e^(At). I have the fundamental solution, which is y(t) = e^(4t)[(5/3); 1] + e^(-t)[0;1] , but how the heck do I get the matrix exponential function e^(At)?