Homework:
4, 5, 12, and 13 from section 8.5 (last two count as challenge problems)
https://ocw.mit.edu/courses/mathematics/18-06-linear-algebra-spring-2010/assignments/MIT18_06S10_pset10_s10_sol.pdf
Lec 31 | MIT 18.06 Linear Algebra, Spring 2005
Lec 29 | MIT 18.06 Linear Algebra, Spring 2005