Question

Rewrite the radical expression as an exponential expression: $\sqrt[3]{2x^8}$

Original question: Rewrite the radical expression as an exponential expression. 2x83\sqrt[3]{2x^8}

(2x)(83)\left(2x\right)^{\left(\frac{8}{-3}\right)}

Expert Verified Solution

thumb_up100%(1 rated)

Key concept: To convert a radical to an exponent, use the rule amn=am/n\sqrt[n]{a^m}=a^{m/n}. Keep the whole radicand under the same fractional exponent.

Step by step

Use the radical-to-exponent rule:

An=A1/n.\sqrt[n]{A}=A^{1/n}.

So

2x83=(2x8)1/3.\sqrt[3]{2x^8}=(2x^8)^{1/3}.

Distribute the exponent to each factor if desired:

(2x8)1/3=21/3x8/3.(2x^8)^{1/3}=2^{1/3}x^{8/3}.

Either form is acceptable, but the direct exponential form is

(2x8)1/3.\boxed{(2x^8)^{1/3}}.

Pitfall alert

Do not write (2x)8/(3)(2x)^{8/(-3)}. The denominator should be positive when converting a cube root, and the radicand should stay inside the fractional exponent as a whole expression.

Try different conditions

If the radical were 2x85\sqrt[5]{2x^8}, the exponential form would be (2x8)1/5(2x^8)^{1/5}. If the radicand were just x8x^8, then the form would be x8/3x^{8/3} after conversion.

Further reading

radical exponent rule, fractional power, cube root

FAQ

What is the exponential form of $\sqrt[3]{2x^8}$?

The exponential form is $(2x^8)^{1/3}$. This comes from the rule $\sqrt[n]{A}=A^{1/n}$.

Can it be written as $2^{1/3}x^{8/3}$?

Yes. By distributing the fractional exponent, $(2x^8)^{1/3}=2^{1/3}x^{8/3}$.

chat