can someone tell me where to start with this problem??
For the following give an example of a relation which is not a function and a relation that is a function
Let A = R and B = Z where R stands for real numbers and Z stands for integers
my professor gave an example of an answer as y = f(x)
f: R --->Z
when f(x) = 2
I really dont know what this means??
Thank you in advance