Explaining y=abs(x) as an Elementary Function

[trelek2]

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]

What are you given for the definition of elementary function? Under the one I am familiar with, y=|x| is not.

 

[trelek2]

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]

I believe that f(x) = |x| is an elementary function. Hint: Express it in terms of squares and square roots.

 

[trelek2]

cheers!

 

[RepoMan]

It is an elementary function. Think of it as |a| = SQRT(a^2)

Wiki gives a great little explanation on it, http://en.wikipedia.org/wiki/Absolute_value"