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 17

Find each value. If applicable, give an approximation to four decimal places. log 0.0022

Verified step by step guidance
1
Recognize that the problem asks for \( \log 0.0022 \), which means the logarithm base 10 of 0.0022.
Rewrite 0.0022 in scientific notation to make the logarithm easier to handle: \( 0.0022 = 2.2 \times 10^{-3} \).
Use the logarithm property \( \log(ab) = \log a + \log b \) to separate the expression: \( \log(2.2 \times 10^{-3}) = \log 2.2 + \log 10^{-3} \).
Recall that \( \log 10^{-3} = -3 \) because \( \log 10^k = k \) for any integer \( k \).
Calculate \( \log 2.2 \) using a calculator or logarithm table, then add it to \( -3 \) to find the final logarithm value. If needed, approximate the result to four decimal places.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4m
Was this helpful?

Key Concepts

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

Definition of Logarithms

A logarithm answers the question: to what exponent must the base be raised to produce a given number? For example, log base 10 of 100 is 2 because 10 squared equals 100. Understanding this helps in converting between exponential and logarithmic forms.
Recommended video:
7:30
Logarithms Introduction

Properties of Logarithms

Logarithms have key properties such as the product, quotient, and power rules that simplify calculations. For instance, log(ab) = log a + log b and log(a^n) = n log a. These properties are useful for breaking down complex logarithmic expressions.
Recommended video:
5:36
Change of Base Property

Evaluating Logarithms of Small Numbers and Approximations

When the argument of a logarithm is a small decimal (less than 1), the logarithm value is negative. Calculators or logarithm tables can approximate these values, often rounded to a specified number of decimal places, such as four decimals in this problem.
Recommended video:
5:14
Evaluate Logarithms