The origin in apolar coordinate systemis also called apole(not to be confused with apole of a functionincomplex analysis, which is anisolated singularity). Every point is defined in terms of anangleand aray(a line that starts at given coordinates and extends to infinity) from the pole. Th...
the cross product will be 0. If both vectors are normalized, and they are perpendicular to each other, the cross product will be 1 (if the angle from a to b is 90°) or -1 (if the angle is 270°).