The position-time equation for a certain train is xf=2.2m + (8.6m/s) t + (2.3m/s2) t2. What is the position of the train in the previous problem at the time 4.9 s?

The position of the train at the time 4.9 seconds is 99.563 meters

Explanation:

* Lets explain how to solve the problem

The position-time equation for a certain train is:

f (x) = 2.2 + 8.6 t + 2.3 t², where f (x) is the position of the train in

meters at a certain time t in second.

We need to find the position of the train at the time 9.4 seconds.

So lets substitute the value of t in the position-time equation.

The position-time equation f (x) = 2.2 + 8.6 t + 2.3 t²

The time = 4.9 seconds

f (x) = 2.2 + 8.6 (4.9) + 2.3 (4.9) ²

f (x) = 2.2 + 42.14 + 55.223

f (x) = 99.563

The position of the train at the time 4.9 seconds is 99.563 meters