The total stopping distance T of a vehicle is shown below,

Last updated: 7/17/2022

The total stopping distance T of a vehicle is shown below, where T is in feet and x is the speed in miles per hour. Approximate the change and percent change in total stopping distance as speed changes from x = 17 to x As speed changes from x = 17 to x = 19 miles per hour, an approximation of the change in x is To approximate the change in total stopping distance, differentiate T = 2.5x + 0.5x² with respect to x and solve for the differential dT. Substitute 17 for x and 2 for dx, to conclude that the approximate change in total stopping distance is as follows.