Question

Rewrite the exponential expression as a radical expression: $-3x^{2/3}$

Original question: Rewrite the exponential expression as a radical expression.

3x2/3-3x^{2/3}

9x23\sqrt[3]{9x^2}

Expert Verified Solution

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Expert intro: This is a power-to-radical conversion problem. Use the rule am/n=amna^{m/n}=\sqrt[n]{a^m} and keep the coefficient outside the radical.

Detailed walkthrough

We rewrite the fractional exponent using the radical rule:

x2/3=x23x^{2/3}=\sqrt[3]{x^2}

Then multiply by the coefficient 3-3:

3x2/3=3x23-3x^{2/3}=-3\sqrt[3]{x^2}

So the radical form is:

3x23\boxed{-3\sqrt[3]{x^2}}

💡 Pitfall guide

A common mistake is putting the coefficient inside the radical as 3x23\sqrt[3]{-3x^2}. That changes the value, because the 3-3 is a separate factor and should stay outside unless the expression specifically asks for it inside.

🔄 Real-world variant

If the expression were 3x5/3-3x^{5/3}, you would rewrite it as 3x53-3\sqrt[3]{x^5}. If the exponent had a different denominator, such as x2/5x^{2/5}, the radical would use a fifth root instead of a cube root.

🔍 Related terms

fractional exponents, radical form, cube root

FAQ

How do you rewrite $-3x^{2/3}$ as a radical expression?

Use the rule $a^{m/n}=\sqrt[n]{a^m}$. Since $x^{2/3}=\sqrt[3]{x^2}$, the expression becomes $-3\sqrt[3]{x^2}$.

Why is $-3$ outside the radical?

The coefficient $-3$ is a separate factor. Moving it inside the radical would change the expression unless it is rewritten carefully as part of the radicand.

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