Examples with solutions for Increasing and Decreasing Intervals of a Function: Identifying which domain is applicable for the described function

Exercise #1

Determine the domain of the following function:

A function describing the charging of a computer battery during use.

Step-by-Step Solution

According to logic, the computer's battery during use will always decrease since the battery serves as an energy source for the computer.

Therefore, the domain that suits this function is - always decreasing.

Answer

Always decreasing

Exercise #2

Determine the domain of the following function:

The function describes a student's grades throughout the year.

Step-by-Step Solution

According to logic, the student's grades throughout the year depend on many criteria that are not given to us.

Therefore, the appropriate domain for the function is - it is impossible to know.

Answer

Impossible to know.

Exercise #3

Determine the domain of the following function:

The function represents the weight of a person over a period of 3 years.

Step-by-Step Solution

Logically, a person's weight is something that fluctuates.

In one week, a person's weight can increase, but in the following week, it can decrease.

Therefore, the domain that suits this function is - partly increasing and partly decreasing.

Answer

Partly increasing and partly decreasing.

Exercise #4

Determine which domain corresponds to the described function:

The function describes a person's energy level throughout the day.

Step-by-Step Solution

Logically, a person's energy level throughout the day changes and depends on many factors.

On one hand, energy levels rise for example when a person eats or consumes caffeine.

On the other hand, energy levels drop when for example a person moves a lot or exercises.

Therefore, the domain that fits this function is - partly increasing and partly decreasing.

Answer

Partly increasing and partly decreasing

Exercise #5

Determine which domain corresponds to the function described below:

The function represents the amount of fuel in a car's tank according to the distance traveled by the car.

Step-by-Step Solution

According to the definition, the amount of fuel in the car's tank will always decrease, since during the trip the car consumes fuel in order to travel.

Therefore, the domain that is suitable for this function is - always decreasing.

Answer

Always decreasing

Exercise #6

Determine which domain corresponds to the function described below:

The function represents the height of a child from birth to first grade.

Step-by-Step Solution

According to logic, a child's height from birth until first grade will always be increasing as the child grows.

Therefore, the domain that suits this function is - always increasing.

Answer

Always increasing.

Exercise #7

Which domain corresponds to the described function:

The function represents the velocity of a stone after being dropped from a great height as a function of time.

Step-by-Step Solution

According to logic, the speed of the stone during a fall from a great height will increase as it falls with acceleration.

In other words, the speed of the stone increases, so the appropriate domain for this function is - always increasing.

Answer

Always increasing