– $x$, $y$, $z$ keńisliginiń bazıbir oblastında berilgen $u=f(x, y, z)$ funkciyası ushın - bul $\dfrac{\partial u}{\partial x}$, $\dfrac{\partial u}{\partial y}$, $\dfrac{\partial u}{\partial z}$ proekciyalarǵa iye vektor bolıp, ol tómendegi simvollar menen belgilenedi: $\text{grad}u=\dfrac{\partial u}{\partial x}\vec{i}+\dfrac{\partial u}{\partial y}\vec{j}+\dfrac{\partial u}{\partial z}\vec{k}$ yamasa $\text{grad}f(x, y, z)$, bunda $\dfrac{\partial u}{\partial x}$, $\dfrac{\partial u}{\partial y}$, $\dfrac{\partial u}{\partial z}$ - dara tuwındılar, $\vec{i}$, $\vec{j}$, $\vec{k}$ - ortlar.