Question

The emergency brake cable in a truck parked on a steep hill breaks and the truck starts rolling down the hill. The distance in feet, d, that the truck rolls is represented by the function d=f(t)=0.5t2. Using this function, find out how far the truck will roll after 9 seconds.

Answer 1

The truck will roll 40.5 feet from top of the hill after 9 seconds.

Explanation:

Let be
`f(t)` the distance rolled by the truck in time, measured in feet, whose expression is:

`f(t) = 0.5\cdot t^(2)`

Where
`t` is the time, measured in seconds.

By evaluating this function at
`t = 9\,s`, we find the distance rolled by the truck:

`f(9\,s) = 0.5\cdot (9\,s)^(2)`

`f(9\,s) = 40.5\,ft`

The truck will roll 40.5 feet from top of the hill after 9 seconds.