Mapping/Take preimage/Complete assignment/Exercise
Let and denote sets. We consider the mapping
which assigns to a mapping the mapping given by taking preimages.
a) Show that is injective.
b) Suppose . Show that is not surjective.
Let and denote sets. We consider the mapping
which assigns to a mapping the mapping given by taking preimages.
a) Show that is injective.
b) Suppose . Show that is not surjective.