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sotellme
Dec14-04, 09:35 AM
directly proportional? can anyone give an example of it?


thanks alot!

Pyrrhus
Dec14-04, 09:40 AM
y and x are directly proportional, A is a constant.

y = Ax

\frac{y}{x} = A

Sirus
Dec14-04, 10:01 AM
Right. This is represented as y\propto x.

sotellme
Dec14-04, 09:23 PM
thanks! :smile:

cyby
Dec14-04, 09:25 PM
Careful. Make sure A is not a positive constant < 1. Otherwise you will get that they are inversely proportional.

sotellme
Dec14-04, 09:29 PM
Careful. Make sure A is not a positive constant < 1. Otherwise you will get that they are inversely proportional.


hi cyby! what you mean with that? do you mean that A must always be a positve number if not it will be inversely proportional? :cry:

Tom Mattson
Dec14-04, 09:31 PM
Careful. Make sure A is not a positive constant < 1. Otherwise you will get that they are inversely proportional.

No, that's not true. It's still a direct proportion. y and x are inversely proportional if y=A/x.

cyby
Dec14-04, 09:32 PM
Uh, you are right. Sorry, was thinking about something else completely.