Example

Simplifying 24x73\sqrt[3]{24x^7} and 80y144\sqrt[4]{80y^{14}}

Apply the Product Property of nnth Roots to simplify two radical expressions whose radicands contain both a non-perfect-power numerical coefficient and a variable raised to a power that is not a multiple of the index. Both the numerical and variable parts must be factored separately to extract the largest perfect nnth power factor.

24x73=2x23x3\sqrt[3]{24x^7} = 2x^2\sqrt[3]{3x}:

The index is 33. Factor the radicand into its largest perfect cube factor and the remainder. For the coefficient: 24=23324 = 2^3 \cdot 3, so the largest perfect cube factor is 23=82^3 = 8. For the variable: the largest multiple of 33 that is at most 77 is 66, so x7=x6xx^7 = x^6 \cdot x. Combine: 24x7=23x63x24x^7 = 2^3 x^6 \cdot 3x. Rewrite the first part as (2x2)3(2x^2)^3:

(2x2)33x3=(2x2)333x3=2x23x3\sqrt[3]{(2x^2)^3 \cdot 3x} = \sqrt[3]{(2x^2)^3} \cdot \sqrt[3]{3x} = 2x^2\sqrt[3]{3x}

Since the index 33 is odd, no absolute value is needed.

80y144=2y35y24\sqrt[4]{80y^{14}} = 2|y^3|\sqrt[4]{5y^2}:

The index is 44. For the coefficient: 80=24580 = 2^4 \cdot 5, so the largest perfect fourth power factor is 24=162^4 = 16. For the variable: the largest multiple of 44 that is at most 1414 is 1212, so y14=y12y2y^{14} = y^{12} \cdot y^2. Combine: 80y14=24y125y280y^{14} = 2^4 y^{12} \cdot 5y^2. Rewrite the first part as (2y3)4(2y^3)^4:

(2y3)45y24=(2y3)445y24=2y35y24\sqrt[4]{(2y^3)^4 \cdot 5y^2} = \sqrt[4]{(2y^3)^4} \cdot \sqrt[4]{5y^2} = 2|y^3|\sqrt[4]{5y^2}

Since the index 44 is even, the variable extracted from the radical requires absolute value signs: (2y3)44=2y3\sqrt[4]{(2y^3)^4} = 2|y^3|. The coefficient 22 does not need absolute value bars because it is always positive.

These examples extend the simplification technique to radicands where neither the numerical coefficient nor the variable exponent is itself a perfect nnth power — both parts require factoring independently before the Product Property can be applied.

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Updated 2026-05-01

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