Chapter 3: Problem 16
For the following exercises, find the domain of each function using interval notation. $$ f(x)=\frac{\sqrt{x+4}}{x-4} $$
Short Answer
Expert verified
Domain: \([-4, 4) \cup (4, \infty)\)
Step by step solution
01
Recognize Function Type and Constraints
The function \( f(x) = \frac{\sqrt{x+4}}{x-4} \) contains a square root in the numerator and a linear expression in the denominator. To find the domain, we need to ensure that all parts of the function are defined. This means:1. The expression \( x+4 \) under the square root must be non-negative.2. The denominator \( x-4 \) cannot equal zero.
02
Determine Square Root Constraint
For the square root expression \( \sqrt{x+4} \) to be defined, the inside, \( x+4 \), must be greater than or equal to zero. Solve the inequality:\[ x+4 \geq 0 \]Subtract 4 from both sides:\[ x \geq -4 \]This means \( x \) must be greater than or equal to \(-4\) for the square root to be valid.
03
Determine Denominator Constraint
The denominator must not be zero to ensure the function is defined at all points:\[ x-4 eq 0 \]Solve this by adding 4 to both sides:\[ x eq 4 \]This means \( x \) cannot be 4.
04
Combine Constraints
Combine the results from Steps 2 and 3 to find the domain of the function. The domain is where both conditions are satisfied:- \( x \geq -4 \)- \( x eq 4 \)So the domain of \( f(x) \) in interval notation is \([-4, 4) \cup (4, \infty)\).
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Square Root Function
The square root function is often represented as \( \sqrt{x} \) in algebra. It involves taking the square root of a number or expression. For the square root function to be defined, the expression inside the square root must be non-negative. This is because square roots of negative numbers are not real. Here are some key points:
- The expression inside the square root (radicand) must be zero or positive.
- Determine the constraints on the variable by solving the inequality for the radicand.
Interval Notation
Interval notation is a mathematical way to represent a range of values for which a function is defined. It's a concise method to describe inequalities related to functions. Here are its components:
- Brackets \( [ ] \) indicate the endpoints are included in the interval.
- Parentheses \( ( ) \) imply the endpoints are not included.
Rational Function
A rational function is expressed as the quotient of two polynomials. The function \( f(x) = \frac{\sqrt{x+4}}{x-4} \) is also a rational function. When dealing with rational functions:
- Identify any restrictions where the denominator equals zero, as these points are undefined.
- Analyze the numerator for additional constraints (like square roots).