Page 290 - 35Linear Algebra

290 Kernel, Range, Nullity, Rank

One-to-one functions are also called injective functions (and sometimes
called monomorphisms.) Notice that injectivity is a condition on the pre-
images of f.
The function f is onto if every element of T is mapped to by some element
of S. That is, f is onto if for any t ∈ T, there exists some s ∈ S such that
f(s) = t. Onto functions are also called surjective functions (and sometimes
epimorphisms.) Notice that surjectivity is a condition on the range of f.

If f is both injective and surjective, it is bijective (or an isomorphism.)

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