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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 51

Find each value. If applicable, give an approximation to four decimal places. ln 28

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1
Recognize that \( \ln 28 \) means the natural logarithm of 28, which is the power to which \( e \) (Euler's number, approximately 2.71828) must be raised to get 28.
Recall the definition: \( \ln x = y \) means \( e^y = x \). So here, \( \ln 28 = y \) means \( e^y = 28 \).
To find \( \ln 28 \), you can use a calculator with a natural logarithm function or logarithm tables.
Enter 28 into the calculator and press the \( \ln \) button to get the value of \( \ln 28 \).
If required, round the result to four decimal places to provide the approximation.

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Key Concepts

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

Natural Logarithm (ln)

The natural logarithm, denoted as ln, is the logarithm to the base e, where e ≈ 2.71828. It answers the question: to what power must e be raised to get a given number? For example, ln(28) finds the exponent x such that e^x = 28.
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Properties of Logarithms

Logarithms have properties that simplify calculations, such as ln(ab) = ln(a) + ln(b) and ln(a^b) = b ln(a). These properties help break down complex expressions or approximate values by using known logarithms.
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Approximation and Rounding

When exact values are difficult to find, logarithms are often approximated using calculators. The problem requests rounding the answer to four decimal places, which means limiting the decimal digits to four after the decimal point for precision.
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