求购:Math2454 textbook: Differential Equations (2ND EDITION) by John Polking, Albert Boggess and David Arnold.
卖:Math1107/2107 textbook & study guide(study guild特别推荐,非常好用): Linear Algebra and its applications (3rd ed.) by David C. Lay, 两本一共 $60 (不讲价,因为我买的是新书,当年花了140刀)
ECON1000 textbook +...