determine the order of the differential equation. 1. x - 3y +4(y") = 0 2. y" - 4y' + 5xy"" = 2 3. xyy" - 2x + xy' = 4y 4. y' = 2y' sin x - 3xy = 5 determine whether the given function is a solution of the differential equation. If this function is a solution, determine whether it satisfies the indicated initial condition. 5. y = 2x2, y' = 2y +4, y(0) = -2 6. y = x, y' = xy 2x, y(1) = 1 7. y = et, y" - 2y' +y = 0, y(0) = 1 8. y = 3 cos 2x, y" + 4y = 0, y(0) = 3