1. Follow the same procedure to confirm that the general solution of the differential equation y"(x) = -y(x) is y(x) = A cos(x) + Bsin(x) for constants A and B. Hint: recall that sin(x) = > (-1)" 2n+1 2n (2n + 1)!" cos(x) = (-1)" n=0 n=0 (2n2)