a) Show: The substitution u(x) = sin(x) + y(a) + 2 makes the differential equa- tion y'(x) + cos(:) = 5 (sin(a) + y(x) + 2)1/5 (* ) separable. b) Solve the differential equation (*) using the substitution u(x) = sin(x) + y() + 2. Also consider the case when separation of variables is not possible: What function do we get in this case as solution? Explicitly check that it is a solution. We will call this solution the additional solution in the following