The position of a particle moving along the x axis varies in time according to the expression x = 6t2, where x is in meters and t is in seconds. Evaluate its position at the following times.
(b) t=2.5s + Δt
(c) Evaluate the limit of Δx/Δt as Δt approaches zero to find the velocity at t = 2.50 s.
The Attempt at a Solution
(a) was simple, just plug in 2.5s and get 37.5m
(b) the problem doesn't explain well enough, but i finally got it, plug in 2.5 + Δt for t and I got 6(2.5 + Δt)^2
(c) I don't even know how to do this, it's been 4 years since I've taken classes of higher math and I must have forgotten most. The answer provided is 30 but I don't know the steps to get there.