2019 THREE(d)

The velocity of an object is modelled by the function

$v=2e^t+8e^{-t}$, for $t\ge 0$

where $v$ is the velocity of the object, in m s${}^{-1}$
and $t$ is the time in seconds since the start of the object’s motion.

Find the time when the acceleration of the object is 0.

*You must use calculus and show any derivatives that you need to find when solving this
problem.*