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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 1

Write ∛64 using exponents and evaluate.

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1
Recall that the cube root of a number can be expressed as an exponent with a fractional power. Specifically, the cube root of a number \(a\) is written as \(a^{\frac{1}{3}}\).
Rewrite the cube root of 64 using this exponent form: \(\sqrt[3]{64} = 64^{\frac{1}{3}}\).
Express 64 as a power of a smaller base if possible. Since \(64 = 2^6\), rewrite the expression as \(64^{\frac{1}{3}} = (2^6)^{\frac{1}{3}}\).
Use the power of a power property of exponents, which states \((a^m)^n = a^{m \times n}\), to simplify the expression: \((2^6)^{\frac{1}{3}} = 2^{6 \times \frac{1}{3}}\).
Multiply the exponents: \(6 \times \frac{1}{3} = 2\), so the expression simplifies to \(2^2\). This is the simplified form of the cube root of 64.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Radicals and Rational Exponents

A radical expression like the cube root (∛) can be rewritten using rational exponents. Specifically, the cube root of a number is the same as raising that number to the power of 1/3. This allows us to convert root expressions into exponent form for easier manipulation.
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Exponentiation Rules

Exponentiation rules govern how to work with powers, including fractional exponents. Understanding that a^(m/n) means the nth root of a^m helps in simplifying expressions. This concept is essential for rewriting and evaluating expressions involving roots and powers.
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Evaluating Powers

Evaluating powers involves calculating the numerical value of an expression with exponents. For example, 64^(1/3) means finding the number which, when cubed, equals 64. Recognizing perfect powers like 64 = 4^3 simplifies the evaluation process.
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