Answered

Evaluate the expression.

$\log_{28} 3910$



(Simplify your answer. Type an integer or decimal rounded to six decimal places as needed.)

Verified Answer :

  • Express the logarithm using the change of base formula: \(\log_{28} 3910 = \frac{\ln 3910}{\ln 28}\).
  • Calculate the values of the natural logarithms \(\ln 3910\) and \(\ln 28\).
  • Divide the two values to obtain the numerical approximation.
  • The final result rounded to six decimal places is \(\boxed{2.482228}\).

Explanation

  1. Understanding the Problem and Data Analysis

The objective is to evaluate the expression \(\log_{28} 3910\) and provide the result rounded to six decimal places. A logarithm \(\log_b a\) represents the power to which the base \(b\) must be raised to equal \(a\). Since \(28^2 = 784\) and \(28^3 = 21952\), we expect the result to be between 2 and 3.

  1. Using the Change of Base Formula

To compute logarithms with bases other than 10 or \(e\) (the natural base), we use the change of base formula:
\[\log_b a = \frac{\ln a}{\ln b}\]
where \(\ln\) denotes the natural logarithm. Applying this to our expression:
\[\log_{28} 3910 = \frac{\ln 3910}{\ln 28}\]

  1. Calculating and Rounding the Result

We now evaluate the natural logarithms of 3910 and 28:
\(\ln 3910 \approx 8.271376\)
\(\ln 28 \approx 3.332205\)
Performing the division:
\[\frac{\ln 3910}{\ln 28} \approx \frac{8.271376}{3.332205} \approx 2.482228\]
The calculation results in approximately \(2.482228\). Since we are asked to round to six decimal places, our result is finalized at this value.

  1. Final Answer

The numerical value of the expression \(\log_{28} 3910\), rounded to six decimal places, is \(\boxed{2.482228}\).

Examples

Logarithms are essential in measuring phenomena that vary across several orders of magnitude. For example, the Richter scale used to measure the intensity of earthquakes is a logarithmic scale. Similarly, in acoustics, sound intensity levels are measured in decibels (dB) using a logarithmic formula, which helps engineers design soundproofing or audio equipment effectively by compressing a vast range of sound pressures into a manageable numerical range. Understanding how to convert and evaluate these logarithmic expressions allows us to accurately interpret these scientific measurements.