3. [a] Find the general solution to the following differential equation. Express your answer in terms of Bessel functions of the rst and second kinds [just as we did in assignments, do not write the asnwers as series expansions of Bessel functions}. Please explain how you arrived at your answer. 2:23;" -| my: -I [35:2 5);.- = D [b] Please solve the heat ow problem. Please, start with the nal formula for arias, it}. Do not use separation of variables. Simplify your answer as much as possible! 3a 321.: at 33:2 u[,t} = u[4.t} = H w a{m,}