- скаляр. Двойное векторное произведение . Положение точки в пространстве определяется радиус – вектором , координаты которого (u1, u2, u3) зависят от принятой системы координат. Положение точки можно однозначно определить пересечением трех поверхностей, семейства которых описываются, как u1=const, u2=const, u3=const. Пересечение двух поверхностей дает координатную линию; значения двух координат на этой линии постоянны, третья меняется. Координаты точки называют криволинейными. Система координат называется ортогональной криволинейной, если касательные к координатным линиям в каждой точке пересекаются под прямым углом. Эти касательные называются координатными осями. Их направление меняется от точки к точке.
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)
Пусть |