# 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.

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" [Broken]

Last edited by a moderator:

### Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving