Relations Examples Page 3

What is the relation described by the equation y = 2x, whose domain is all negative integers?

Having a "domain'' of negative integers means that x, the first thing in each ordered pair, has to be a negative integer. It's like starting out by getting all the bad news out of the way before moving on to the good news. At least, we hope there's going to be some good news...

We get the relation

{(-1, -2), (-2, -4), (-3, -6), (-4, -8). . .}

Uh-oh. Looks like nothing but bad news. We knew we shouldn't have stopped wearing our lucky socks.