Image And Preimage Notation. To decide if this function is onto we need to determine if every element in the codomain has a preimage in the domain. Take any real number x in mathbb r choose a b 2x 0.
The image of the function f is a c. Notation for image and inverse image. To tell them apart they will usually be defined separately.
To tell them apart they will usually be defined separately.
The image is the result of performing a transformation and the preimage is the original that you perform the transformation. R r defined by f x x 2. The preimage of a is f 1 a 1 2. 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.