Question

Assume that f:l-->R is a coordinate function. Prove that -f is also a coordinate function.

Answer 1

what's I? The unit interval?

Answer 2

l is a line

Answer 3

So it's a line in R^2 and the function maps a point on the line to either its x or y ordinate?

Answer 4

I think so. Sorry all the book says is the first thing that I wrote.

Answer 5

We're going to need a sharper definition of coordinate function.

Answer 6

A coordinate function is one to one, onto, and satisfies the eqn sqrt((x2-x1)^2+(y2-y2)^2))