Question

The position of an object at time t is given by s(t) = -9 - 3t. Find the instantaneous velocity at t = 8 by finding the derivative.

Answer 1

This is the power rule
I wrote the first note that the derivative of constant is zero
And then the derivative of t is 1 if we apply the rule with n=1
And since we have -3 in the front of t, the derivative of -3t is -3*1=-3
This is the derivative of the position function
And it is also the inst. velocity
Actually the velocity is always -3, no matter what t is
It means that it is driving in the opposite direction