If [tex]\( x \)[/tex] is a positive integer, for how many different values of [tex]\( x \)[/tex] is [tex]\( \sqrt{\frac{48}{x}} \)[/tex] a whole number?

A. 2
B. 3
C. 6
D. 10



Answer :

To determine for how many different values of [tex]\( x \)[/tex] will [tex]\( \sqrt{\frac{48}{x}} \)[/tex] be a whole number, let's go through the problem step by step:

1. Expression Simplification:
We need [tex]\( \sqrt{\frac{48}{x}} \)[/tex] to be a whole number. Let [tex]\( k \)[/tex] represent this whole number:
[tex]\[ \sqrt{\frac{48}{x}} = k \][/tex]
Squaring both sides gives us:
[tex]\[ \frac{48}{x} = k^2 \][/tex]

2. Solve for [tex]\( x \)[/tex]:
Rearrange the equation to solve for [tex]\( x \)[/tex]:
[tex]\[ x = \frac{48}{k^2} \][/tex]
For [tex]\( x \)[/tex] to be a positive integer, [tex]\( \frac{48}{k^2} \)[/tex] must also be an integer. Therefore, [tex]\( k^2 \)[/tex] must be a divisor of 48.

3. Find the Divisors:
Let's find the divisors of 48 that are perfect squares.

First, list the divisors of 48:
[tex]\[ 1, 2, 3, 4, 6, 8, 12, 16, 24, 48 \][/tex]

Next, identify which of these are perfect squares:
[tex]\[ 1, 4, 16 \][/tex]

4. Determine Values of [tex]\( x \)[/tex]:
- For [tex]\( k^2 = 1 \)[/tex]: [tex]\( x = \frac{48}{1} = 48 \)[/tex]
- For [tex]\( k^2 = 4 \)[/tex]: [tex]\( x = \frac{48}{4} = 12 \)[/tex]
- For [tex]\( k^2 = 16 \)[/tex]: [tex]\( x = \frac{48}{16} = 3 \)[/tex]

Each value of [tex]\( k^2 \)[/tex] gives us a valid [tex]\( x \)[/tex].

5. Conclusion:
The values of [tex]\( x \)[/tex] that make [tex]\( \sqrt{\frac{48}{x}} \)[/tex] a whole number are 48, 12, and 3. There are 3 such values.

Hence, the answer is [tex]\(\boxed{3}\)[/tex].