The expression you've provided seems to describe a velocity function $v(t)$ over a time interval $[4, 8]$. Specifically:

$v(t) = 6 - \frac{t}{4} \quad \text{for} \quad 4 \leq t \leq 8.$

Would you like to find the displacement, distance traveled, or analyze the behavior of this function over the given time interval? Please specify what you'd like to explore.

Here are some options:

1. Calculate the displacement over the interval $[4, 8]$.
2. Find the total distance traveled over the interval $[4, 8]$.
3. Determine the time at which the velocity is zero.
4. Analyze whether the velocity is increasing or decreasing over the interval.
5. Graph the velocity function over the given time interval.

Tip: When analyzing motion, displacement considers the direction of travel, while the total distance accounts for the magnitude regardless of direction.