# Combining Functions

Published on: by Chegg

## Introduction

In this video, we will discuss how to combine functions by exploring examples such as f + g, f - g, f * g, and more. By understanding these concepts, you will be able to apply them to different mathematical problems.

## Defining f + g

To define f + g, we first need to know the functions f(x) and g(x). In the given example, f(x) = 2x - 3 and g(x) = x^2 + 1. To find f + g, we plug in these functions into the formula and simplify the expression. By combining like terms, we get f + g = x^2 + 2x - 2. This is the result of adding the two functions f and g.

The process of defining f + g involves substituting the functions f(x) and g(x) into the formula and performing the necessary arithmetic operations. By following the steps carefully and keeping track of each term, we arrive at the final expression for f + g. Understanding how to combine functions like f and g is essential in mathematics, especially in the context of function composition and other mathematical operations.

## Defining f - g

In order to define f - g, we start by knowing the functions f(x) and g(x) as given in the example: f(x) = 2x - 3 and g(x) = x^2 + 1. Substituting these functions into the formula for f - g, we carefully perform the subtraction operation. After simplifying the expression by combining like terms, we obtain f - g = -x^2 + 2x - 4. This represents the result of subtracting the functions f and g.

Defining f - g requires precision in substituting the functions into the formula and accurately subtracting the terms. By understanding the fundamentals of function operations, such as addition and subtraction, one can enhance their problem-solving skills in mathematics. The process of defining f - g contributes to a deeper comprehension of function manipulation and mathematical concepts.

## Defining f * g

To define f * g, we need to utilize the functions f(x) = 2x - 3 and g(x) = x^2 + 1 provided in the example. By substituting these functions into the formula for f * g and performing the multiplication, we obtain the expression for the product of f and g. After expanding and combining like terms, we arrive at f * g = 2x^3 - 3x^2 + 2x - 3, showcasing the result of multiplying the functions f and g.

The process of defining f * g involves the systematic multiplication of the terms corresponding to the functions f(x) and g(x). By following the mathematical operations carefully and simplifying the expression correctly, one can determine the product of two functions effectively. Understanding the concept of multiplication between functions offers valuable insights into mathematical operations and function manipulation.

## Defining f / g

Defining f / g requires the knowledge of the functions f(x) = 2x - 3 and g(x) = x^2 + 1 provided in the example. By substituting these functions into the formula for f / g and performing the division operation, we can determine the quotient of f and g. In this case, f / g simplifies to (2x - 3) / (x^2 + 1), representing the division of f by g.

The process of defining f / g involves executing the division operation correctly and simplifying the resulting expression. By understanding the principles of function division and applying them to specific examples like f(x) and g(x), individuals can enhance their mathematical reasoning skills. Defining f / g contributes to a deeper understanding of function relationships and mathematical concepts.

## Exploring function compositions: f o g, g o f, and g o g

Exploring function compositions involves understanding the concepts of f o g, g o f, and g o g. By considering the functions f(x) = 2x - 3 and g(x) = x^2 + 1 provided in the example, we can determine these compositions. Calculating f o g, g o f, and g o g requires substituting the functions into the respective composition formulas and evaluating the expressions to obtain the final results.

Function compositions like f o g, g o f, and g o g play a crucial role in mathematical analysis and problem-solving. By exploring different compositions of functions and understanding how they interact with each other, individuals can gain valuable insights into function relationships and mathematical operations. The process of exploring function compositions enhances one's ability to manipulate functions and expand their mathematical proficiency.

## Highlights

- Understanding the basics of combining functions
- Applying the concept of function compositions in mathematical problems
- Learning the step-by-step process of finding f + g, f - g, f * g, and f / g
- Mastering the techniques of simplifying expressions involving functions
- Improving problem-solving skills through practice and application

## FAQ

**Q: What is the definition of f + g?**

A: The definition of f + g is obtained by adding the values of f(x) and g(x) for each x in the domain.

**Q: How do you find f * g?**

A: To find f * g, multiply the values of f(x) and g(x) together for each x in the domain.

**Q: What is function composition?**

A: Function composition is a mathematical operation that combines two functions to create a new function.

**Q: What are the key steps in simplifying function expressions?**

A: The key steps in simplifying function expressions involve replacing variables with their corresponding functions, performing operations according to the function definitions, and simplifying the resulting expression.

**Q: How can combining functions be applied in real-life scenarios?**

A: Combining functions can be applied in various fields such as engineering, physics, and computer science to model and analyze complex systems and relationships.