Image And Preimage Definition. Onto functions focus on the codomain. What does preimage mean.
Images and preimages of sets. Image and inverse image may also be defined for general binary relations not just functions. Roughly speaking you might think of f x as a kind of distorted copy or image of x in b the preimage f 1 y of y is the set of all things in a that f sends into y.
For example the square abcd when translated four units right becomes square a b c d.
Preimage of a set. Preimage the original figure in a transformation. The image is the result of performing a transformation and the preimage is the original that you perform the transformation. X y is any function not necessarily invertible the preimage or inverse image of an element.