Solutions for Problem Set 1 out + some info

The solutions for Problem Set 1 are available on Canvas. Please do not distribute them further. Many of you submitted solutions and generally all the submission were pretty good. Refer to the posted solution for an indication of how I might structure an answer. Keep up the good work! 

Also, I noticed that many of you retyped the text of the problems themselves. You are not required to do this (unless you want to of course); I already know what the question is!