Problem 22 - College Algebra and Calculus: An Applied Approach

Question

Write the logarithm in terms of natural logarithms.\(\log _{x} \frac{3}{4}\)

Step-by-Step Solution

Answer

\(\log _{x} \frac{3}{4}\) in terms of natural logarithms is \(\frac{\ln(\frac{3}{4})}{\ln(x)}\)

Step 1: Apply Change of Base Formula

First, apply the change of base formula to convert the base of the logarithm to e (the base of natural logarithms). This gives: \(\log {x} \frac{3}{4} = \frac{\ln(\frac{3}{4})}{\ln(x)}\).

Step 2: Result

Therefore, the logarithm \(\log {x} \frac{3}{4}\) in terms of natural logarithms is \(\frac{\ln(\frac{3}{4})}{\ln(x)}\). This is the final answer.

Key Concepts

Understanding Logarithms

Logarithms are powerful mathematical tools used to simplify complex expressions and solve equations involving exponents. Understanding what a logarithm represents will help you manage base changes, like switching to natural logarithms. The expression \(\log_b(a)\) represents an exponent \(x\), such that \(b^x = a\). Here, \(b\) is the base of the logarithm, and \(a\) is the number you're taking the logarithm of. For example, \(\log_2(8) = 3\) because \(2^3 = 8\). Logarithms are critical in various fields such as engineering, science, and finance. When dealing with different bases, the change of base formula becomes handy, allowing the conversion to more manageable logarithm forms, such as natural logarithms with base \(e\).

Exploring Natural Logarithms

Natural logarithms are logarithms with base \(e\), where \(e\) is approximately 2.71828. It is a special mathematical constant that appears frequently in calculus and is the foundation for continuous growth and decay models.The natural logarithm of a number \(x\) is written as \(\ln(x)\). Natural logarithms are particularly significant in calculus and mathematical analysis because they have simple derivatives and integrals. For instance, the derivative of \(\ln(x)\) is \(\frac{1}{x}\), and the integral is \(x \ln(x) - x + C\), where \(C\) is the constant of integration.Using natural logarithms allows for simplifying computations with exponential functions, making them a preferred choice in many scientific and engineering contexts.

Simplifying Mathematical Expressions

Mathematical expressions often need simplification for easier interpretation or computation. By employing methods such as the change of base formula, complex logarithms can be rewritten in more manageable forms.For example, the expression \(\log_x \frac{3}{4}\) can be simplified using the change of base formula, converting it into natural logarithms:

• Use the formula: \(\log_b(a) = \frac{\ln(a)}{\ln(b)}\).
• Apply it: \(\log_x \frac{3}{4} = \frac{\ln(\frac{3}{4})}{\ln(x)}\).

This approach not only simplifies the expression but makes it easier to work within problems involving calculus or complex arithmetic.Understanding these simplifications is critical for tackling real-world problems that involve exponential growth, decay, or other logarithmic-based methodologies.