At a certain time instant, the vector vec$(a)(t)$ has

vec$(a)=-3$hat$()m$

vec$(a{)}^{}=-2$hat$()-4$hat$()\frac{m}{s}.$

Matlab$/$Octave Mathematica Python R

SymPy

from sympy import $**$

$a=$Matrix$([0,-3,0])$

aDot $=$Matrix$([-2,-4,0])$

At this same instant of time, what is vec$(a{)}^{}(t)*hat(a)(t)?$

vec$(a{)}^{}(t)*hat(a)(t)=$

$?\frac{m}{s}$