Example

Writing x\sqrt{x}, y3\sqrt[3]{y}, and z4\sqrt[4]{z} with Rational Exponents

Convert three radical expressions into rational exponent form by applying the equivalence an=a1n\sqrt[n]{a} = a^{\frac{1}{n}} in the radical-to-exponent direction.

x=x12\sqrt{x} = x^{\frac{1}{2}}: When a square root has no index written, the index is 22 by convention. The index becomes the denominator of the rational exponent, so x=x12\sqrt{x} = x^{\frac{1}{2}}.

y3=y13\sqrt[3]{y} = y^{\frac{1}{3}}: The index is 33, so the denominator of the exponent is 33. The expression becomes y13y^{\frac{1}{3}}.

z4=z14\sqrt[4]{z} = z^{\frac{1}{4}}: The index is 44, so the denominator of the exponent is 44. The expression becomes z14z^{\frac{1}{4}}.

In each case, the conversion follows the same pattern: the radicand becomes the base, and the index of the radical becomes the denominator of the fractional exponent 1n\frac{1}{n}. This is the reverse of writing a rational exponent as a radical — both directions use the same rule a1n=ana^{\frac{1}{n}} = \sqrt[n]{a}.

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Updated 2026-04-21

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