Math 611, Fall 2011. Instructor P. Kuchment HW #2. 2 points per a problem Due September 30th General remarks: • Write solutions neatly and not in microscopic letters. Avoid many crossing outs, etc. This is not only for me to read easier, but for you to be sure that what you write is correct. I will not grade in the future proofs that are messily written and unreadable due to a tiny letter size. • Avoid words “trivial ..., easy to see ..., obvious ...” and other their synonyms. “Easy to see” or “trivial” should mean that you can show this in a second, so just do it :-). By the way, errors are usually appearing in “obvious” places. • Be careful with parentheses and other such standard rules; they can cause mistakes if not followed properly. • Make sure you understand your logic completely. If you don’t, I won’t. :-) Problems: 1. Solve problems ## 1, 2, 3, 4, 8, 10 from Section 2.5 (pages 84-87) of the textbook. Extra credit problems. 2 points per a problem. No partial credit 2. Solve problems ## 5, 11 from Section 2.5 (pages 84-87) of the textbook. 3. The stationary single-speed radiative transport equation without scattering on the plane R2 is ω · ∇u(x) + µ(x)u(x) = f (x). Suppose that one shoots photons with the itensity u = I0 from the origin in the direction of the vector ω. The detector is located some distance l away in this direction. Solve the equation and find what will be the intensity of the received signal u = I1 at the detector. 1