Particle's acceleration when it achieves maximum displacement in the +x direction I'm not sure if this goes in the physics section or the mathematics section, but this question seems pretty math oriented, so I'll ask it here.
$t\ge0$ and $v_x=24-3t^3$
I have to find the particle's acceleration when it achieves maximum displacement in the $+x$ direction. I'm not sure how to know exactly when the particle hits maximum displacement.

HINT:
Maximum displacement occurs at the time when the velocity reaches zero.  (Why?  You can think either from a physical perspective or a mathematical one.)
And acceleration is the derivative of the velocity with respect to time.
Can you proceed now?
