Question

true or false, neither the absolute value function nor the greatest integer function is one to one. ( i know i asked already just can't view the answers)

Answer 1

Are there more than one input that give the same output?

What are the possible solutions to: |x| = 3
What are the possible solutions to g(x) = 3
(where g is the greatest integer function)

Answer 2

in R \[\left| x \right|\] is not 1:1 but in {x | x > 0] |x| is 1:1. The g(x) however is not 1:1 a simple counter example is consider g(a,y) = y than for all y=b < y g(b,y) = y. Hence this is not 1:1. It does give a nice latice theoretic ordering though.