精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰常微分方程導論 課程性質︰系必修 課程教師︰林紹雄 開課學院:理學院 開課系所︰數學系 考試日期(年月日)︰2010年10月12日 考試時限(分鐘):50分鐘 是否需發放獎勵金:是 試題 : There are problems A to B with a total 50 points. Please write down your comp- utational or proof steps clearly on the answer sheets. A. Solve the following ODE. (a) (10 points) y''' - 4y' = 2t + 3(cos t)^2 +e^(-2t) y(0) = 0 , y'(0) = -1 , y''(0) = 0. (b) (20 points) The homogeneous equation ty'' + (5t-1) y' - 5y = 0 has a solu- tion of the form y1(t) = at +b. Then solve the inhomogeneous equation ty'' + (5t-1)y' -5y = t^2 * e^(-5t)/ (c) (8 points) (t^3)y''' + (t^2)y'' - 2ty' + 2y = 0 in t > 0. B.It is known that t,t^2 and t^3 are three solutions of the ODE y'' +p(y)y' + q(t)y = f(t). (a) (7 points) Find a basis of solutions for the corresponding homogeneous eq- uation. Then solve the ODE with initial conditions y(2) = 2 ,y'(2) = 5. (b) (5 points) Find p(t) explicitly. -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.112.251.220