Question

Fan and medal! Can a function be nonlinear? How do you determine if a relation is a function?

Answer 1

yes it can be quadratic, or polynomial, or logarithmic, ....

Answer 2

A relation is a function iff for every value of x there's only one value of y.
"A relation for which each element of the domain corresponds to exactly one element of the range."

Answer 3

That's what I thought... Can you help me with the how can you determine a function bit? And can you explain how the vertical line test works?

Answer 4

Ohh okay thank you!!

Answer 5

do you still need help with "Can you help me with the how can you determine a function bit?" or anything else here?

Answer 6

Just the vertical line test I think, they explained it to me very strangely.

Answer 7

where did they explain it to you, can you paste the question link here?

Answer 8

I can't, sorry, it's in a lesson (I'm working on a printed paper) and the website shuts down around this time :/

Answer 9

is this a function ?

Answer 10

@formerlyadinosaur

Answer 11

Uhhh I think no because there is there is more than one output for each input right?

Answer 12

so you draw a vertical line thru the 3 thickened dots and that's you vertical line test, do you understand it now?

Answer 13

here is another example

Answer 14

Sort of? I might be way of the peg uhmm Soooo if it follows a vertical line it isn't a function?

Answer 15

Oh wait so if more than one point crosses the vertical line it isn't a function?

Answer 16

above we have 3 orange vertical lines, all 3 cross the graph in 2 points, so this is now a function. If all possible vertical lines cross the graph ONLY in 1 point then its a function, ok?

Answer 17

your obeservations is correct

Oh wait so if more than one point crosses the vertical line it isn't a function?

Answer 18

Okay, I get it I think (: thanks!

Answer 19

welcome