\chapter{Exponentials and logarithms} \section{Exponential equations}
Check your understanding
Answer the questions. \begin{enumerate} \item Explain the difference between the two exponential equations: \[2^{x+1}=8\] \[3^{x+1}=8\] and the best method to solve them \item Suppose we want to solve the equation \(5^{2x+1}=9\), and we want to know a decimal approximation of the answer with two decimal places. We consider two methods: the translation formula for logarithms, or taking \(\ln\) of both sides. Explain why we cannot use the first method. \item To solve the equation \(3 e^{x+8}= 5\), we took \(\ln\) of both sides, and we found \[\ln \left( 3 e^{x+8} \right) = \ln 5\] What is the second step? (i) Use property (C) of the logarithms: \(\ln x^y=y\ln x\) (ii) Use the simplification formula \(\ln e^x = x\) (iii) Use property (A) of the logarithms: \(\ln(xy) = \ln x + \ln y\). \item We are solving a certain exponential equation, and we reached the following equation: \[3x \ln 4 -x \ln3 = 1+\ln 3.\] What is the next step? \end{enumerate}
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