Week 12

Here are some links and resources for the 12th (including Monday November 23 before thanksgiving) week of the course:
In lecture 29, we looked at explicit Zeta sums like 1+2+3+ ...+ n or 12+22+32 + .. + n2. There are explicit formulas for that. More generally, one can look at 1-s+2-s+3-s + .. + n-s and especially look at the limit when n going to infinity. This is the zeta function ζ(s) = 1-s+2-s+3-s + ... . In the following movie, we look at the roots of this function by plotting 1/zeta(s). One needs calculus to make sense of expressions like ζ(-1) = 1+2+3+4+.... . The limit is (it should surprise you) -1/12. See the Numberphile movie. The plotting is done in Google earth:

Poll from lecture 29

This is a good poll. It exposes a misconception. The correct answer is B and was not always chosen by the majority in both sections. The problem of An article in MAA.

Poll from lecture 30

Also this poll shows that already just getting the meaning the fundamental theorem of calculus can be tricky. In this case, the correct answer is B.

Poll from lecture 31

Poll from lecture 32