Q$1)$ Find the the directional derivative of $$:$x^{3}yz+3x{y}^{2}z$ at the point $(3,-1,2)$ in the direction $e_x-2e_y-2e_z$

Ans check: grad$*r=\frac{-48}{\sqrt[\phantom{2}]{9}}$

Q$2)$ Referring to Q$1,$ assuming all variables are applicable.

Find the Laplacian or $($:grad$*grad\}$

Ans check: $)=(6xyz+6xy$