If is a set consisting of elements ( may be equal to ), it is called pair, where be the 1st component and be the second component, then we call be ordered pair and written as .
If are non-empty sets, then their Cartesian product, denoted by i.e.,
The product is known as Cartesian Plane.
is three dimensional space.
be non-empty sets, where is element of
is known as – tuples.