Table of contents
- 0. Review of Algebra4h 16m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 6m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 19m
- 10. Combinatorics & Probability1h 45m
3. Functions
Intro to Functions & Their Graphs
Problem 77b
Textbook Question
In Exercises 76–81, find the domain of each function. g(x) = 4/(x - 7)

1
Identify the function: \( g(x) = \frac{4}{x - 7} \).
Recognize that the function is a rational function, which means it is a fraction with a polynomial in the denominator.
Understand that the domain of a function is the set of all possible input values (x-values) that will not cause the function to be undefined.
Determine when the denominator is zero, as this will make the function undefined. Set the denominator equal to zero: \( x - 7 = 0 \).
Solve the equation \( x - 7 = 0 \) to find the value of \( x \) that is not in the domain. The domain of \( g(x) \) is all real numbers except this value.

This video solution was recommended by our tutors as helpful for the problem above
Video duration:
1mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Domain of a Function
The domain of a function refers to the set of all possible input values (x-values) for which the function is defined. For rational functions, the domain is typically restricted by values that would make the denominator zero, as division by zero is undefined.
Recommended video:
Domain Restrictions of Composed Functions
Rational Functions
A rational function is a function that can be expressed as the ratio of two polynomials. In the case of g(x) = 4/(x - 7), the numerator is a constant (4) and the denominator is a linear polynomial (x - 7). Understanding the structure of rational functions is essential for determining their domains.
Recommended video:
Intro to Rational Functions
Finding Restrictions
To find the domain of a function, one must identify any restrictions on the input values. For g(x) = 4/(x - 7), the restriction arises from the denominator, which cannot equal zero. Thus, solving the equation x - 7 = 0 reveals that x cannot be 7, leading to the conclusion that the domain excludes this value.
Recommended video:
Restrictions on Rational Equations
Watch next
Master Relations and Functions with a bite sized video explanation from Nick Kaneko
Start learningRelated Videos
Related Practice