# The position of a particle moving along the $x$-axis ($x$ is in $m$) is given by $x = t^3 - 3t^2 + 2t$. Find the velocity of the particle at $t=2\;s$.

Given $x = t^3 - 3t^2 + 2t$.
Velocity $v(t) = \large\frac{dx}{dt}$$= 3t^2 - 6t + 2$
$\Rightarrow v(2) = 3 \times 2^2 - 6 \times 2 + 2 = 2\;m/s$