Open-Ended: For the expression [tex]$x^{\frac{3}{2}}$[/tex], is there a difference between doing [tex]$(\sqrt{x})^3$[/tex] or [tex][tex]$\sqrt{x^3}$[/tex][/tex]? Explain with examples.

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Answer :

To analyze whether there is a difference between doing [tex]\((\sqrt{x})^3\)[/tex] or [tex]\(\sqrt{x^3}\)[/tex] for the expression [tex]\(x^{\frac{3}{2}}\)[/tex], let's go through a detailed explanation with an example.

Let's take [tex]\(x = 4\)[/tex].

1. Calculate [tex]\((\sqrt{x})^3\)[/tex]:
- First, find the square root of [tex]\(x\)[/tex].
[tex]\[ \sqrt{4} = 2 \][/tex]
- Then, raise this result to the power of 3.
[tex]\[ (2)^3 = 8 \][/tex]
Thus, [tex]\((\sqrt{4})^3 = 8\)[/tex].

2. Calculate [tex]\(\sqrt{x^3}\)[/tex]:
- First, raise [tex]\(x\)[/tex] to the power of 3.
[tex]\[ 4^3 = 64 \][/tex]
- Then, find the square root of this result.
[tex]\[ \sqrt{64} = 8 \][/tex]
Thus, [tex]\(\sqrt{4^3} = 8\)[/tex].

From both methods, we see that:

[tex]\[ (\sqrt{4})^3 = 8 \quad \text{and} \quad \sqrt{4^3} = 8 \][/tex]

Therefore, there is no difference in the result between [tex]\((\sqrt{x})^3\)[/tex] and [tex]\(\sqrt{x^3}\)[/tex] for the expression [tex]\(x^{\frac{3}{2}}\)[/tex]. Both methods yield the same final answer.

To generalize, for any non-negative [tex]\(x\)[/tex], we have:

[tex]\[ (\sqrt{x})^3 = \sqrt{x^3} \][/tex]

This can be understood from the property of exponents:

[tex]\[ x^{\frac{3}{2}} = \left(x^{\frac{1}{2}}\right)^3 = \left(x^3\right)^{\frac{1}{2}} \][/tex]

which confirms that both methods [tex]\((\sqrt{x})^3\)[/tex] and [tex]\(\sqrt{x^3}\)[/tex] will indeed yield the same result.