Below are tables for two functions,
[math] and
[math] The function
[math] is
invertible, but the function
[math] is
noninvertible.
Invertible function [math]

Noninvertible function [math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

[math]

In the last problem, you decided why a certain table was noninvertible.
In general, a function is noninvertible if:
In general, a function is invertible if:
Hint:
Solution: