# Which of the following sets of points would give functions?

1. May 12, 2004

### cygnus_x1

ok... this is the thing... i've got a math assignment due tomorrow and i need help!!! argh.. its on functions so if theres anybody who can help me, please do..

if you could, would you help me with this question:

"Which of the following sets of points would give functions? Explain your answer."
{(1,4),(2,5),(3,6),(4,7),(5,8)}

i'd really appreciate it...
thx

2. May 12, 2004

### chroot

Staff Emeritus
I'm not sure I understand the question. There seems to be only one set. Further, "points" don't necessarily have anything to do with functions. I assume that the first member of the pairs is in the domain of a function, and the second member is the range -- but I'm still not sure what it means to "give a function."

Can you provide more context on how this question was presented?

- Warren

3. May 13, 2004

### HallsofIvy

A list of (x,y) pairs certainly can give a function. In a sense it is y= f(x) where x must be one of the first numbers in the pairs and y is the second number in that same pair. A "function" specifically has the property that you do not have the same "x" (first number) with two different "y"s (second number). That is, you cannot have, for example, (3, 7) and (3, 5) in the same "function". Since, in the example given, the first numbers are 1, 2, 3, 4, 5 with no repeats, it IS a function.