Edexcel P3 2022 June — Question 4

Exam BoardEdexcel
ModuleP3 (Pure Mathematics 3)
Year2022
SessionJune
TopicExponential Equations & Modelling

4. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{44035bf8-f54c-472a-b969-b4fa4fa3d203-10_677_839_251_516} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} The number of subscribers to an online video streaming service, \(N\), is modelled by the equation $$N = a b ^ { t }$$ where \(a\) and \(b\) are constants and \(t\) is the number of years since monitoring began.
The line in Figure 1 shows the linear relationship between \(t\) and \(\log _ { 10 } N\)
The line passes through the points \(( 0,3.08 )\) and \(( 5,3.85 )\) Using this information,
  1. find an equation for this line.
  2. Find the value of \(a\) and the value of \(b\), giving your answers to 3 significant figures. When \(t = T\) the number of subscribers is 500000 According to the model,
  3. find the value of \(T\)