Mathematics-I (3110014)

Q5 (a) Winter-2019   Find the directional derivatives of $\mathrm{f}={\mathrm{xy}}^2+{\mathrm{yz}}^2$ at the point $\left(2,-1,1\right)$, in the direction of $\mathrm{i}+2\mathrm{j}+2\mathrm{k}$.