Given the function [tex]\( f(x) = \sqrt{x + 5} - 1 \)[/tex], choose the correct domain written using interval notation.

A. [tex]\((-5, \infty)\)[/tex]

B. [tex]\((- \infty, -5)\)[/tex]

C. [tex]\([-5, \infty)\)[/tex]

D. [tex]\((- \infty, -5]\)[/tex]



Answer :

To determine the domain of the function [tex]\( f(x) = \sqrt{x+5} - 1 \)[/tex], we need to ensure that the expression inside the square root is non-negative. This is because the square root function is only defined for non-negative numbers.

Let's analyze the expression [tex]\( x + 5 \)[/tex]:

1. Non-Negativity Condition:
[tex]\[ x + 5 \geq 0 \][/tex]

2. Solving for [tex]\( x \)[/tex]:
[tex]\[ x + 5 \geq 0 \\ x \geq -5 \][/tex]

3. Interpreting the Result:
- The inequality [tex]\( x \geq -5 \)[/tex] means that [tex]\( x \)[/tex] can be any number greater than or equal to [tex]\(-5\)[/tex].

4. Domain in Interval Notation:
- The domain includes all [tex]\( x \)[/tex] values that are greater than or equal to [tex]\(-5\)[/tex].
- In interval notation, this is written as:
[tex]\[ [-5, \infty) \][/tex]

Therefore, the correct domain of the function [tex]\( f(x) = \sqrt{x+5} - 1 \)[/tex] written in interval notation is:
[tex]\[ \boxed{[-5, \infty)} \][/tex]