\chapter{Exponentials and logarithms} \section{Logarithms }
Check your understanding
Answer the questions in your own words. \begin{enumerate} \item Explain what \(\log_a x\) is. \item What is the difference between \(\log_3 x\), \(\log x\) and \(\ln x\)? \item The following logarithms can all be found without a calculator, except one. Which one? \[ \begin{array}{ccccc} \mbox{(a) } \log_2 32 & \hspace{1ex} \mbox{(b) } \displaystyle\log \frac{1}{10} & \hspace{1ex} \mbox{(c) } \ln\sqrt{e} & \hspace{1ex} \mbox{(d) } \log_2 10 & \hspace{1ex} \mbox{(e) } \log_3 1 \end{array} \] \item The following logarithms can all be found without using the change of base formula, except one. Which one? \[ \begin{array}{ccccc} \mbox{(a) } \log 32 \hspace{1ex} & \mbox{(b) } \displaystyle\log_2 \frac{1}{8} & \hspace{1ex} \mbox{(c) } \log_5 15 & \hspace{1ex} \mbox{(d) } \ln 3 & \hspace{1ex} \mbox{(e) } \log_9 81 \end{array} \] \item Suppose \(x\) is a number greater than \(1\). Arrange the following in increasing order: \[ \begin{array}{cccc} \mbox{(a)} \log_2 x \hspace{1ex} & \mbox{(b)} \displaystyle\log x & \hspace{1ex} \mbox{(c)} \log_5 x & \hspace{1ex} \mbox{(d)} \ln x \end{array} \] \end{enumerate}
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