Think you’ve got your head wrapped around **Differential Equations**? Put your knowledge to
the test. Good luck — the Stickman is counting on you!

Q. Which of the following is not a differential equation?

Q. Determine the order of the differential equation *f* ^{4}(*x*) + *f* ^{(2)}(*x*) = 5 - *f* ^{(3)}(*x*) + *f* (*x*)

1

2

3

4

Q. A *solution* to a differential equation is

a function that satisfies that differential equation.

a number that satisfies that differential equation.

a function that satisfies that differential equation and some additional constraint.

the highest derivative in that differential equation.

Q. The function

*y* = *x*^{2}

is a solution to which one of the following differential equations?

2*y* = *y*'

2*y* = *xy*'

Q. Determine which of the following functions is NOT a solution to the d.e. *f* ^{(2)}(*x*) = -*f* (*x*).

Q. Determine which of the following functions is a solution to the IVP *y*" = *y* and *y*(0) = 1.

Q. Determine which of the following is the particular solution to the IVP *y*" = 8.

Q. Determine which differential equation best represents the following English statement:

The monkey population is increasing at a rate of 1 percent.

Q. Julianna spends 20 per week. If M represents Julianna's money and *t* represents time measured in years, which differential equation best describes this situation?

Q. A family of rabbits has a birth rate of 25 percent. Every year 10 rabbits die. Which of the following differential equations best models this situation?