# Questions

## Online teaching

• Q: how does the course continue in distance form?
Also: A lot has been said about it ( also in class. We try to keep it simple. The classes are done using Zoom. Some class content like handouts will be posted here on the website. A reminder about the meeting will be sent out before each meeting. Homework and exams will be submitted via Canvas. The homework for unit 18 already will be submitted electronically. The deadline for that homework is Monday, March 23 until class starts. I encourage to ask individual questions also by email, any time.

## Week 1:

• Q: What is the difference between exp(x) and ex.
Answer: it is the same. It is the exponential function. We will define it as a limit of exph (1+h)x/h, which is an important function because it is the "compoound interest rate function", which you should be familiar with if you interested in finance. Here is the Wikipedia entry. We use it in a more streamlined form and use the letter h, because in physics, the Planck constant is denoted by h. Nature seems not to like numbers smaller than say h=10-34, the physical reality starts to change there. The interest rate formula appears in the movie "The Bank", where it is written as FutureValue = InitialValue (1+r)n, where r is the interest rate and n is the number of years.
• Q: How do we determine whether a function is invertible from A to B.
Answer: this will be easier in the future when we can differentiate, for now, draw the graph of the function in the rectangle which has the interval A as a base and the interval B as a side. The graph is the graph of a function if the vertical line test is valid. Draw any vertical line. It should pass through exactly one point in the graph. If also the horizontal line test is valid and every horizontal line intersects the graph once, then the function is invertible.
• Q: How much work load do we expect?
Answer: It is a matter of fact that every math course requires a substantial amount of work. Besides attending lectures, there is homework due every class (5 problems each time). Take the homework seriously. It is 30 percent of the grade. We keep the workload constant over the semester and have self-contained handouts and worksheets for every lecture. There are 2 midterms and one final exam.