→ t0444564 :已收錄 03/06 13:54
課程名稱︰偏微分方程導論
課程性質︰數學系必修
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︰2013年03月01日,08:10-09:10
考試時限:60分鐘
是否需發放獎勵金:是
試題 :
Math 2206 (Introdution to PDE) Quiz No.1 (3/01/2013)
Name ID number Department
Solve the follwing problems. Please write down your computational or proof
steps clearly on the answer sheets.
2 2 2
A. (35 points) Consider the first order PDE u ((u_x) + (u_y) ) = 1 with the
Cauchy data u = 1 on the line y = x. Find all admissible initial data on
the line y = x, and determine which admissible data are non-characteristc.
Find all possible solutions.
3
B. Let F(x,y,z,p,q) be C . The PDE F(x,y,u,u_x,u_y) = 0 has the Cauchy data
u(x,y) = h(x,y) along the curve Γ defined by Γ:g(x,y) = 0, where g and h
are C^2 function, and ▽g(x,y)≠0 on Γ.
(a) (5 points) If P = (x*,y*,z*,p*,q*) is an admissible data, write down
the equations satisfied by P.
(b) (10 points) If P in (a) exists, what is the condition for P to be
non-characteristic?
All answers should be expressed in terms of F,g,h at P.
C. Determine which of the following statements is true. Prove your anwser.
Each has 10 points.
1 2 2
(a) There exists u∈C(G) such that u_x + u_y = 0 and u(x,y) = y on x + y = 1,
where G = {(x,y)∈R^2 | 1/2 < x^2 + y^2 < 3/2}.
2 3 2
(b) The Cauchy problem 3xy (u_x) - y (u_y) = 3y / (2x) with Cauchy data
u(x,y) = -y^3 on the curve xy^3 = 1 has infinitely many solutions.
註:教授把characteristic誤打為charateristic,這篇已修正了。
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