1. This document contains solutions to several calculus exercises involving differential equations. 2. One exercise involves solving the differential equation y'' + 9y = 0, which has general solution y(x) = c1sin3x + c2cos3x. 3. Another exercise involves solving the non-homogeneous differential equation y'' + y' = 2e^2x/csc3x, yielding the general solution y(x) = c1 + c2e^-x + (1/5)e^2x(sinx - cosx).