I have uploaded a revised version of homework sheet 2 in which minor typos have been corrected. There are two such typos:
(1) In problem 1, I changed the phrasing from "find" the phase portrait to "plot" the phase portrait to make it clearer.
(2) In problem 2c, I made the definition of q-twisted state more explicit, even though it was actually there anyway.
Neither of these typos should have caused any problems.
Update (2/01/10): There is an additional typo that might be a bit problematic. In problem 3, omega_1 = omega_3 starting in part (b). I inadvertently forgot to type that and hope that this has not caused any problems. I also found a minor typo in (3), which I have corrected (there is a factor of K missing in the denominator in the definition of rho).