Perform the indicated operations and/or simplify each expression. Assume all variables represent positive real numbers.
Table of contents
- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations1h 43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 5m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 22m
- 10. Combinatorics & Probability1h 45m
0. Review of Algebra
Radical Expressions
Problem 148
Textbook Question
Perform the indicated operations and/or simplify each expression. Assume all variables represent positive real numbers.
Verified step by step guidance1
Rewrite each cube root in the denominators as an exponent of 1/3. For example, express \(\sqrt[3]{2}\) as \$2^{1/3}\(, \)\sqrt[3]{16}\( as \)16^{1/3}\(, and \)\sqrt[3]{54}\( as \)54^{1/3}\(. This gives the expression: \)\frac{5}{2^{1/3}} - \frac{2}{16^{1/3}} + \frac{1}{54^{1/3}}$.
Simplify the radicands where possible by expressing them as products of prime factors or perfect cubes. For example, \$16 = 2^4\( and \)54 = 2 \times 3^3\(. Use this to rewrite the cube roots: \)16^{1/3} = (2^4)^{1/3} = 2^{4/3}\( and \)54^{1/3} = (2 \times 3^3)^{1/3} = 2^{1/3} \times 3$.
Rewrite each term using the simplified exponents: \(\frac{5}{2^{1/3}} - \frac{2}{2^{4/3}} + \frac{1}{2^{1/3} \times 3}\). This will help in combining like terms later.
Find a common denominator for all three terms. Since the denominators involve powers of 2 and possibly 3, the common denominator will be the least common multiple of \$2^{1/3}\(, \)2^{4/3}\(, and \)2^{1/3} \times 3$. Express each term with this common denominator.
Combine the numerators over the common denominator by performing the indicated addition and subtraction. After combining, simplify the numerator if possible, and write the final expression as a single fraction.
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
7mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Properties of Radicals and Cube Roots
Understanding how to work with cube roots is essential, including simplifying expressions like ∛16 or ∛54 by factoring under the radical. Recognizing that cube roots can be expressed as fractional exponents (e.g., ∛x = x^(1/3)) helps in manipulation and simplification.
Recommended video:
Imaginary Roots with the Square Root Property
Operations with Fractions
Performing addition and subtraction with fractions requires finding a common denominator. In this problem, the denominators involve cube roots, so identifying a common radical denominator or rewriting terms with a common base is necessary to combine the fractions correctly.
Recommended video:
Guided course
Performing Row Operations on Matrices
Simplification of Expressions with Variables and Radicals
Simplifying expressions involving radicals and variables includes reducing radicals to simplest form and combining like terms. Since variables represent positive real numbers, this allows for certain simplifications, such as removing absolute value considerations and applying standard radical rules.
Recommended video:
Guided course
Radical Expressions with Variables
Related Videos
Related Practice
Textbook Question
711
views
