During the quiz you may use your textbook, my notes, and your own notes. No calculators or other electronic devices are permitted. Please make sure your cell phones are quiet during class and off during quizzes. 12-22-2010: Sorry for leaving in this next paragraph. Given the sample questions below, it obviously doesn't apply. This quiz will only cover material in "Solution of ODEs, BVPs, Part 1" of the course notes, and the corresponding material in the textbook. Part 2 of the notes will not be included. For Quiz 3, be able to: -- Construct a finite difference or finite element approximation to a given ODE-BVP. -- Use the discrete maximum principle for ODE-BVPs. -- Show that if a(u,phi_j) = (f, phi_j) for j = 1,...,M-1, then a(u,v) = (f,v) for all v in S_h. -- Use the error formulas for FD/FE approximations to ODE-BVPs to draw conclusions about how fast the error will decrease. -- Use Theorem 5.2. -- Suppose we change the boundary conditions from u(0)=u(1)=0 to u'(0)=u'(1)=0. Assume that b(x) = 0 and c(x) > 2 for x in [0,1]. The solution exists. Write the weak formulation. (Use test functions v in H^1.) What can you conclude about existence and uniqueness of the solution to the weak problem? Write the linear systems corresponding to finite difference and finite element approximations to this problem. What can you say about existence and uniqueness of the discrete solutions? How close are they to the solution to the ODE? -- Compare and contrast finite difference and finite element methods for solving ODE-BVPs. For example: -- Which requires less work to form and solve the linear system? -- Which should be used if we want to compute an approximation to u'? -- For each method, what can we do if we decide that we need to reduce the error? (reduce h? increase the order of approximation?) -- Apply the Maximum Principle and the Minimum Principle to draw conclusions about the behavior of the solution to an elliptic PDE. -- Use Theorem 3.2. -- Define uniqueness and stability of the solution of an elliptic PDE