Testing For Functions Part 2

Section 1.4
Questions 9 & 10

See attachment.

I don't quite get this one. I'm sure it's easy.

 

actually set A represents input (x values) and set B represents output (y values)

take a close look to given ordered pairs and find what ordered pairs represent a function
recall: A function is a set of ordered pairs in which no two different ordered pairs have the same x -coordinate.

9.
a) { (0,1),(1,-2),(2,0),(3,2) }

10.
b) { (a,1),(b,2),(c,3) }

 

I see it now. Thanks. I got confused with Set A and B..