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trelek2
Nov11-10, 02:52 PM
I have looked up what an elementary function is but I'm still stuck with showing that
y=abs(x) is one.

Can anyone explain how to show this?

mathman
Nov11-10, 04:00 PM
What are you given for the definition of elementary function? Under the one I am familiar with, y=|x| is not.

trelek2
Nov11-10, 05:01 PM
Well, can't see how it is either. Its just that the problems says I have to show that it is.
I looked the definition up on wikipedia.


Maybe I'm supposed to write that it isn't?

Petek
Nov11-10, 05:06 PM
I believe that f(x) = |x| is an elementary function. Hint: Express it in terms of squares and square roots.

trelek2
Nov11-10, 05:49 PM
cheers!

RepoMan
Nov12-10, 09:12 PM
It is an elementary function. Think of it as |a| = SQRT(a^2)

Wiki gives a great little explanation on it, here is the link. (http://en.wikipedia.org/wiki/Absolute_value)