Injective, Surjective, Bijective

domain size

7

range size

7

random seed

268

In the function mapping

xf(x)

, the domain is all

x

values and the range is all

f(x)

values.

If

f(a)=f(b)

implies

a=b

, the function is called injective, or one-to-one.

If for any

y

in the range there is an

x

in the domain so that

f(x)=y

, the function is called surjective, or onto.

If both conditions are met, the function is called bijective, or one-to-one and onto.

Ed Pegg Jr