Solve the exponential equation. Express the solution in terms of natural logarithms or common logarithms. Then use a calculator to obtain a decimal approximation for the solution.



10^x = 3.66

Verified Answer :

  • Apply the definition of the common logarithm to the equation \(10^x = 3.66\) to get \(x = \log_{10}(3.66)\).
  • Utilize the change-of-base formula to express the solution in terms of natural logarithms: \(x = \frac{\ln(3.66)}{\ln(10)}\).
  • Calculate the decimal value to find \(x \approx 0.5635\).
  • Final Answer: \(\boxed{\log(3.66) \approx 0.5635}\).

Explanation

  1. Isolating x using the Logarithm Definition

To solve the exponential equation \(10^x = 3.66\), we first recognize that the variable \(x\) is in the exponent. The most direct way to isolate \(x\) when the base is \(10\) is to apply the common logarithm (\(\log_{10}\)) to both sides of the equation. By the definition of the logarithm, the statement \(b^y = z\) is equivalent to \(y = \log_b(z)\). In our case, \(b = 10\), \(y = x\), and \(z = 3.66\), so we can write \(x = \log_{10}(3.66)\).

  1. Expressing the Solution using Natural Logarithms

Alternatively, we can express the solution using natural logarithms (\(\ln\)). Applying the property \(\log_b(a) = \frac{\ln(a)}{\ln(b)}\), we convert the common logarithm \(\log_{10}(3.66)\) into natural logarithms:
\[x = \frac{\ln(3.66)}{\ln(10)}\]
This expression is equivalent to our previous result and is often useful in scientific calculations.

  1. Calculating the Numerical Value

Finally, we calculate the decimal approximation for the value of \(x\). Using numerical methods, we find that:
\[x = \log_{10}(3.66) \approx 0.563481\]
Rounding to a standard number of decimal places, we have \(x \approx 0.5635\). Thus, the solution set is \(\boxed{\log(3.66) \approx 0.5635}\).

Examples

Exponential equations appear frequently in fields like chemistry and biology, for instance, when calculating the pH of a solution or modeling bacterial population growth. In chemistry, the pH of a liquid is defined as \(pH = -\log_{10}([H^+])\), which can be rewritten as the exponential form \(10^{-pH} = [H^+]\). Solving such equations allows us to determine the concentration of hydrogen ions based on the acidity of a solution, helping scientists understand how chemical environments affect biological processes.