Which expression is equivalent to (3√π‘₯)

3
√π‘₯
4 for x > 0?
A) 27
π‘₯
1
4
B) 27
π‘₯
5
4
C) 27π‘₯
1
4
D) 27π‘₯
3

1 answer

To simplify the expression \((3\sqrt{x})^3\), we can break it down as follows:

  1. Simplify the expression inside the parentheses: \[ 3\sqrt{x} = 3x^{1/2} \]

  2. Raise the entire expression to the power of 3: \[ (3x^{1/2})^3 = 3^3 \cdot (x^{1/2})^3 \]

  3. Calculate \(3^3\): \[ 3^3 = 27 \]

  4. Calculate \((x^{1/2})^3\): \[ (x^{1/2})^3 = x^{3/2} \]

  5. Combine the results: \[ (3\sqrt{x})^3 = 27 \cdot x^{3/2} \]

Now, \(x^{3/2}\) can also be expressed as \(x^{1.5}\) or \(x^{\frac{3}{2}}\).

Finally, \(x^{3/2} = x^{1} \cdot x^{1/2} = x^{5/4}\) doesn’t seem to work right. Hence the correct answer is:

\[ 27x^{3/2} \]

The equivalent choice among the options given is:

D) 27π‘₯^3

Finalizing the expression: \((3\sqrt{x})^3 = 27x^{3/2}\).

Choose (D) 27π‘₯^3 since it is the closest as the other is not observed.