2. x^ 2y" - 2xy' + 2y = x^3 sinx
3. y" + 4y' + 4y = e^-2x
4. y' + 2y = y^2
5. x^2y" - 3xy' + 3y = 3lnx-4
五題~感謝
更新1:
4.5 differential equations/ 1.2.3 general solution
