Domain Of A Function Vs Preimage
To decide if this function is onto we need to determine if every element in the codomain has a preimage in the domain.
Domain of a function vs preimage. Take any real number x in mathbb r choose a b 2x 0. This function maps ordered pairs to a single real numbers. As nouns the difference between domain and preimage is that domain is a geographic area owned or controlled by a single person or organization while preimage is mathematics the set containing exactly every member of the domain of a function such that the member is mapped by the function onto an element of a given subset of the codomain of the function formally of a subset b of the codomain y under a function ƒ the subset of the domain x defined by.
The image of an ordered pair is the average of the two coordinates of the ordered pair.