**Readings Questions:**

You should first read questions 1-4, and then read section
1 completely. Then you will be ready to answer the reading questions thoroughly.
**Always
keep the answers to the reading questions on a separate piece of paper;
these will be randomly collected from time to time.**

1) What is a first-order differential equation? To clarify your definition give several examples which fit your definition and several which do not fit your definition.

2) Give a real world problem which can be interpreted by a first-order differential equation. Then use the 3-step mathematical modeling described on page 4 to analyze your problem.

3) Consider example 4 on page 3

a) Explain
why there is a negative sign in these differential equations.

b) Are these
differential equations first-order differential equation? Explain.

4) What is an initial value problem? Give an example of an initial value problem which is not of first-order. What is the order of your example and why?

5) Extend exercise 13-16 on page 9 to determine possible solutions of a differential equation of the form:

**page 9
3, 5, 11, 13, 14, 15, 16, 21, 24, 25, 32, 35, 40, 41, 43**