8.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{44035bf8-f54c-472a-b969-b4fa4fa3d203-26_579_467_219_749}
\captionsetup{labelformat=empty}
\caption{Figure 4}
\end{figure}
Figure 4 is a graph showing the velocity of a sprinter during a 100 m race.
The sprinter's velocity during the race, \(v \mathrm {~ms} ^ { - 1 }\), is modelled by the equation
$$v = 12 - \mathrm { e } ^ { t - 10 } - 12 \mathrm { e } ^ { - 0.75 t } \quad t \geqslant 0$$
where \(t\) seconds is the time after the sprinter begins to run.
According to the model,
- find, using calculus, the sprinter's maximum velocity during the race.
Given that the sprinter runs 100 m in \(T\) seconds, such that
$$\int _ { 0 } ^ { T } v \mathrm {~d} t = 100$$
- show that \(T\) is a solution of the equation
$$T = \frac { 1 } { 12 } \left( 116 - 16 \mathrm { e } ^ { - 0.75 T } + \mathrm { e } ^ { T - 10 } - \mathrm { e } ^ { - 10 } \right)$$
The iteration formula
$$T _ { n + 1 } = \frac { 1 } { 12 } \left( 116 - 16 \mathrm { e } ^ { - 0.75 T _ { n } } + \mathrm { e } ^ { T _ { n } - 10 } - \mathrm { e } ^ { - 10 } \right)$$
is used to find an approximate value for \(T\)
Using this iteration formula with \(T _ { 1 } = 10\)
- find, to 4 decimal places,
- the value of \(T _ { 2 }\)
- the time taken by the sprinter to run the race, according to the model.