Questions: Radicals Domain of a square root function: Advanced
Find the domain of the function. g(x) = sqrt(28+7x)
Write your answer using interval notation.
Transcript text: Radicals
Domain of a square root function: Advanced
Find the domain of the function.
\[
g(x)=\sqrt{28+7 x}
\]
Write your answer using interval notation.
Solution
Solution Steps
To find the domain of the function \( g(x) = \sqrt{28 + 7x} \), we need to ensure that the expression inside the square root is non-negative. This means solving the inequality \( 28 + 7x \geq 0 \). The solution to this inequality will give us the domain of the function in interval notation.
Step 1: Determine the Condition for the Square Root
The function \( g(x) = \sqrt{28 + 7x} \) involves a square root. For the square root to be defined, the expression inside the square root must be non-negative. Therefore, we need to solve the inequality:
\[
28 + 7x \geq 0
\]
Step 2: Solve the Inequality
To solve the inequality \( 28 + 7x \geq 0 \), we first isolate \( x \):
\[
7x \geq -28
\]
Next, divide both sides by 7:
\[
x \geq -4
\]
Step 3: Write the Domain in Interval Notation
The solution to the inequality \( x \geq -4 \) indicates that the domain of the function \( g(x) \) is all \( x \) values greater than or equal to \(-4\). In interval notation, this is expressed as:
\[
[-4, \infty)
\]
Final Answer
The domain of the function \( g(x) = \sqrt{28 + 7x} \) is \(\boxed{[-4, \infty)}\).