Cauchy Mean Value Theorem/Example

Example of Use of Cauchy Mean Value Theorem
In the 2012 Olympics Usain Bolt won the 100 metres gold medal with a time of $9.63$ seconds.

By definition, his average speed was the total distance travelled divided by the total time it took:

The Mean Value Theorem gives:
 * $\map {f'} c = \dfrac {\map f b - \map f a} {b - a}$

Hence, at some point Bolt was actually running at the average speed of $37.38 \ \mathrm {km/h}$

Asafa Powell was participating in that same race.

He achieved a time of $11.99 \ \mathrm s = 1.245 \times 9.63 \ \mathrm s$.

So Bolt's average speed was $1.245$ times the average speed of Powell.

The Cauchy Mean Value Theorem gives:

Hence, at some point, Bolt was actually running at a speed exactly $1.245$ times that of Powell's.