Example

Simplifying 4x3+4x3\sqrt[3]{4x} + \sqrt[3]{4x} and 4842844\sqrt[4]{8} - 2\sqrt[4]{8}

Simplify two expressions involving higher roots that are already like radicals.

4x3+4x3=24x3\sqrt[3]{4x} + \sqrt[3]{4x} = 2\sqrt[3]{4x}:

Both terms are cube roots with the same radicand 4x4x, so they are like radicals. Each term has an implicit coefficient of 11. Add the coefficients: 1+1=21 + 1 = 2.

4x3+4x3=24x3\sqrt[3]{4x} + \sqrt[3]{4x} = 2\sqrt[3]{4x}

484284=2844\sqrt[4]{8} - 2\sqrt[4]{8} = 2\sqrt[4]{8}:

Both terms are fourth roots with the same radicand 88, so they are like radicals. Subtract the coefficients: 42=24 - 2 = 2.

484284=2844\sqrt[4]{8} - 2\sqrt[4]{8} = 2\sqrt[4]{8}

In both parts, the radicals share the same index and radicand, so only the coefficients are combined while the radical factor remains unchanged — the same approach used when combining like square roots or like terms in algebra.

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Updated 2026-04-21

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