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Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 1, Problem 103

Perform the indicated operations. Assume all variables represent positive real numbers. 2∛16 + ∛54

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1
Rewrite each cube root expression in terms of prime factors or simpler components. For example, express \(\sqrt[3]{16}\) and \(\sqrt[3]{54}\) using their prime factorizations: \$16 = 2^4$ and \(54 = 2 \times 3^3\).
Use the property of cube roots that \(\sqrt[3]{a^b} = a^{\frac{b}{3}}\) to simplify each term. For instance, \(\sqrt[3]{2^4} = 2^{\frac{4}{3}}\) and \(\sqrt[3]{2 \times 3^3} = \sqrt[3]{2} \times \sqrt[3]{3^3} = \sqrt[3]{2} \times 3\).
Rewrite the original expression \(2 \sqrt[3]{16} + \sqrt[3]{54}\) using the simplified forms from step 2, so it becomes \(2 \times 2^{\frac{4}{3}} + 3 \times \sqrt[3]{2}\).
Factor out the common cube root term \(\sqrt[3]{2} = 2^{\frac{1}{3}}\) from both terms to combine them. This means expressing each term as a multiple of \(2^{\frac{1}{3}}\).
After factoring, combine the coefficients and write the expression as a single term involving \(\sqrt[3]{2}\). This completes the simplification of the original expression.

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Key Concepts

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