**Question:**
A particle moves on the positive x-axis. The particle is moving towards the origin

when it passes through the point

, where

, with speed

, where

is constant. Given that the particle experiences an acceleration

in a direction away from

, show that it come instantaneously to rest at a point

, where

. Immediately the particle reaches B the acceleration changes to

in a direction away from

. Show that the particle next comes instantaneously to rest at

.

**My Problem with this question:**
I have no idea on how to approach it. Please help. Thanks in advance.