Solving Problems with the Function

Oct 13, 2025 by wbrum.org 50 views

Introduction

In this article, we will be discussing a function D(t) that defines a traveler's distance from home, in miles, as a function of time, in hours. The function is defined in three different intervals, each with its own unique equation. We will explore the function, its domain, and its range, and discuss the implications of the function's behavior.

The Function D(t)

The function D(t) is defined as:

D(t)=\left{\begin{array}{cl} 300 t+125, & 0 \leq t\ \textless \ 2.5 \ 875, & 2.5 \leq t \leq 3.5 \ 75 t+612.5, & 3.5\ \textless
t\end{array}\right.

This function is a piecewise function, meaning that it is defined in multiple parts. The first part of the function, 300t + 125, is defined for 0 ≤ t < 2.5. The second part of the function, 875, is defined for 2.5 ≤ t ≤ 3.5. The third part of the function, 75t + 612.5, is defined for t > 3.5.

Domain and Range

The domain of a function is the set of all possible input values for which the function is defined. In this case, the domain of the function D(t) is the set of all real numbers t such that 0 ≤ t < 2.5, 2.5 ≤ t ≤ 3.5, or t > 3.5.

The range of a function is the set of all possible output values for which the function is defined. In this case, the range of the function D(t) is the set of all real numbers y such that y ≥ 125, 875 ≤ y ≤ 875, or y ≥ 612.5.

Graphing the Function

To graph the function D(t), we need to graph each part of the function separately. The first part of the function, 300t + 125, is a linear function that passes through the point (0, 125) and has a slope of 300. The second part of the function, 875, is a constant function that is equal to 875 for all values of t between 2.5 and 3.5. The third part of the function, 75t + 612.5, is a linear function that passes through the point (3.5, 875) and has a slope of 75.

Analyzing the Function

To analyze the function D(t), we need to examine its behavior in each of the three intervals. In the first interval, 0 ≤ t < 2.5, the function is increasing at a rate of 300 miles per hour. In the second interval, 2.5 ≤ t ≤ 3.5, the function is constant at 875 miles. In the third interval, t > 3.5, the function is increasing at a rate of 75 miles per hour.

Conclusion

In conclusion, the function D(t) is a piecewise function that defines a traveler's distance from home, in miles, as a function of time, in hours. The function is defined in three different intervals, each with its own unique equation. We have analyzed the function's domain and range, graphed the function, and examined its behavior in each of the three intervals. This function has many real-world applications, such as modeling the distance traveled by a car or a plane.

Real-World Applications

The function D(t) has many real-world applications, such as modeling the distance traveled by a car or a plane. For example, if a car is traveling at a constant speed of 60 miles per hour, the function D(t) can be used to model the distance traveled by the car as a function of time. Similarly, if a plane is flying at a constant speed of 500 miles per hour, the function D(t) can be used to model the distance traveled by the plane as a function of time.

Solving Problems with the Function

To solve problems with the function D(t), we need to use the function's equation and the given information to find the solution. For example, if we know that the traveler is 875 miles away from home at time t = 3, we can use the function's equation to find the time at which the traveler was 125 miles away from home.

Practice Problems

Here are some practice problems to help you understand the function D(t) and its applications:

Find the distance traveled by a car that is traveling at a constant speed of 60 miles per hour for 2.5 hours.
Find the time at which a plane is 875 miles away from home if it is flying at a constant speed of 500 miles per hour.
Find the distance traveled by a traveler who is 125 miles away from home at time t = 0 and is traveling at a constant speed of 300 miles per hour.

Conclusion

Q: What is the function D(t)?

A: The function D(t) is a piecewise function that defines a traveler's distance from home, in miles, as a function of time, in hours.

Q: What are the three intervals of the function D(t)?

A: The three intervals of the function D(t) are:

0 ≤ t < 2.5
2.5 ≤ t ≤ 3.5
t > 3.5

Q: What is the equation for the first interval of the function D(t)?

A: The equation for the first interval of the function D(t) is 300t + 125.

Q: What is the equation for the second interval of the function D(t)?

A: The equation for the second interval of the function D(t) is 875.

Q: What is the equation for the third interval of the function D(t)?

A: The equation for the third interval of the function D(t) is 75t + 612.5.

Q: What is the domain of the function D(t)?

A: The domain of the function D(t) is the set of all real numbers t such that 0 ≤ t < 2.5, 2.5 ≤ t ≤ 3.5, or t > 3.5.

Q: What is the range of the function D(t)?

A: The range of the function D(t) is the set of all real numbers y such that y ≥ 125, 875 ≤ y ≤ 875, or y ≥ 612.5.

Q: How do I graph the function D(t)?

A: To graph the function D(t), you need to graph each part of the function separately. The first part of the function, 300t + 125, is a linear function that passes through the point (0, 125) and has a slope of 300. The second part of the function, 875, is a constant function that is equal to 875 for all values of t between 2.5 and 3.5. The third part of the function, 75t + 612.5, is a linear function that passes through the point (3.5, 875) and has a slope of 75.

Q: How do I analyze the function D(t)?

A: To analyze the function D(t), you need to examine its behavior in each of the three intervals. In the first interval, 0 ≤ t < 2.5, the function is increasing at a rate of 300 miles per hour. In the second interval, 2.5 ≤ t ≤ 3.5, the function is constant at 875 miles. In the third interval, t > 3.5, the function is increasing at a rate of 75 miles per hour.

Q: What are some real-world applications of the function D(t)?

A: The function D(t) has many real-world applications, such as modeling the distance traveled by a car or a plane. For example, if a car is traveling at a constant speed of 60 miles per hour, the function D(t) can be used to model the distance traveled by the car as a function of time. Similarly, if a plane is flying at a constant speed of 500 miles per hour, the function D(t) can be used to model the distance traveled by the plane as a function of time.

Q: How do I solve problems with the function D(t)?

A: To solve problems with the function D(t), you need to use the function's equation and the given information to find the solution. For example, if we know that the traveler is 875 miles away from home at time t = 3, we can use the function's equation to find the time at which the traveler was 125 miles away from home.

Q: What are some practice problems that I can use to help me understand the function D(t)?

A: Here are some practice problems that you can use to help you understand the function D(t):

Find the distance traveled by a car that is traveling at a constant speed of 60 miles per hour for 2.5 hours.
Find the time at which a plane is 875 miles away from home if it is flying at a constant speed of 500 miles per hour.
Find the distance traveled by a traveler who is 125 miles away from home at time t = 0 and is traveling at a constant speed of 300 miles per hour.