Answer to Question #238835 in Discrete Mathematics for lavanya

Question

Determine whether the following relations are injective and/or subjective function. Find universe of the  functions if they exist.

i.     A= v,w,x,y,z, B=1,2,3,4,5

       R= (v,z),(w,1), (x,3),(y,5)

Answer 1

Solution:

Given, A= v,w,x,y,z, B=1,2,3,4,5

       R= (v,z),(w,1), (x,3),(y,5)

Clearly, R does not contain any element for z in A. Thus, it is neither injective nor surjective.

Hence, its inverse won't exist.