Skip to main content
Ch. 4 - Inverse, Exponential, and Logarithmic Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 5, Problem 23

Solve each equation. x=log884x = \(\log\)_8 \(\sqrt\)[4]{8}

Verified step by step guidance
1
Recognize the given equation: \(x = \log_{8} \sqrt[4]{8}\). The goal is to solve for \(x\).
Rewrite the fourth root as a fractional exponent: \(\sqrt[4]{8} = 8^{\frac{1}{4}}\).
Substitute this back into the logarithm: \(x = \log_{8} \left(8^{\frac{1}{4}}\right)\).
Use the logarithm power rule: \(\log_{a} (b^{c}) = c \cdot \log_{a} b\). So, \(x = \frac{1}{4} \cdot \log_{8} 8\).
Since \(\log_{8} 8 = 1\) (because the base and the argument are the same), simplify to find \(x = \frac{1}{4}\).

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1m
Was this helpful?

Key Concepts

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

Logarithms and Their Properties

A logarithm answers the question: to what exponent must the base be raised to produce a given number? For example, log₈(8) = 1 because 8¹ = 8. Understanding how to interpret and manipulate logarithms is essential for solving equations involving them.
Recommended video:
5:36
Change of Base Property

Radicals and Fractional Exponents

Radicals like the fourth root (∜) can be expressed as fractional exponents, such as ∜8 = 8^(1/4). Converting radicals to exponents simplifies calculations and helps in applying logarithmic rules effectively.
Recommended video:
Guided course
05:45
Radical Expressions with Fractions

Change of Base and Simplification Techniques

Simplifying logarithmic expressions often involves rewriting numbers with common bases or using properties like log_b(a^c) = c·log_b(a). Recognizing these allows for easier evaluation of expressions like log₈(8^(1/4)) by bringing the exponent out front.
Recommended video:
5:36
Change of Base Property