9709 P31 - Nov 2017 - Q2
1580
Two variable quantities x and y are believed to satisfy an equation of the form \(y = C(a^x)\), where \(C\) and \(a\) are constants. An experiment produced four pairs of values of x and y. The table below gives the corresponding values of x and \(\\ln y\).
\(\begin{array}{c|cccc} x & 0.9 & 1.6 & 2.4 & 3.2 \\ \hline \\ln y & 1.7 & 1.9 & 2.3 & 2.6 \end{array}\)
By plotting \(\\ln y\) against x for these four pairs of values and drawing a suitable straight line, estimate the values of \(C\) and \(a\). Give your answers correct to 2 significant figures.
