3.108: Particle with ln\mathrm{ln} displacement

0606/23/O/N/23 — Question 6 · 9 marks

A particle travels in a straight line. Its displacement, ss metres, from the origin at time tt seconds, where t2t \geqslant 2, is given by s=ln(4t25)ts = \mathrm{ln}(4t^{2} - 5) - t.
(a)
Find expressions for the velocity, vms1v\,\mathrm{ms}^{-1}, and acceleration, ams2a\,\mathrm{ms}^{-2}, of the particle.
[4]
(b)
Find the time when the particle is at rest.
[3]
(c)
Find the acceleration at this time.
[2]