Exercise 38.9.2 Solve the linear differential equation $2dy | 21133; = 611:2 do: as (a) a homogeneous differential equation (b) an exact differential equation. Exercise 38.9.3 Find the general solution of the following equations by any ap- propriate method: (b) Solve the following differential equation by changing the dependent variable from y to u = arctan(y): (1 + y') = (arctan(y) - x) dy dx