What is the domain of the function [tex]\( y = 2 \sqrt{x-6} \)[/tex] ?

A. [tex]\( -\infty \ \textless \ x \ \textless \ \infty \)[/tex]

B. [tex]\( 0 \leq x \ \textless \ \infty \)[/tex]

C. [tex]\( 3 \leq x \ \textless \ \infty \)[/tex]

D. [tex]\( 6 \leq x \ \textless \ \infty \)[/tex]



Answer :

To determine the domain of the function [tex]\( y = 2 \sqrt{x - 6} \)[/tex], we need to consider the conditions under which the function is defined.

1. Square Root Condition: The square root function [tex]\( \sqrt{x-6} \)[/tex] is defined only when the expression inside the square root, [tex]\( x - 6 \)[/tex], is non-negative. This is because the square root of a negative number is not a real number.

2. Non-Negativity: For [tex]\( \sqrt{x-6} \)[/tex] to be valid:
[tex]\[ x - 6 \geq 0 \][/tex]

3. Solving the Inequality: Solving this inequality:
[tex]\[ x - 6 \geq 0 \implies x \geq 6 \][/tex]

Therefore, the domain of the function [tex]\( y = 2 \sqrt{x - 6} \)[/tex] is all [tex]\( x \)[/tex] such that [tex]\( x \geq 6 \)[/tex].

In set notation, the domain can be expressed as:
[tex]\[ [6, \infty) \][/tex]

So, the correct choice is:
[tex]\( 6 \leq x < \infty \)[/tex].