Wierd symbol what is it?

1. Nov 1, 2007

futurebird

My prof writes this symbol that looks (sort of) like this $$\ni$$ for "such that"

I just write the words "such that" in my notes...

But what is this symbol? I just choose the latex that looked most like what's on the board... is it the right one?

2. Nov 2, 2007

Gib Z

Well in set builder notation usually $$\in$$ means "in" and "|" for "such that". Eg $$S=\{ k \in \mathbb{Q} | \sqrt{k} \in \mathbb{C} \}$$ means the set S is equal to the set of rational numbers such that sqrt k is a complex number.

3. Nov 2, 2007

leon1127

I was introduced with this notation back when i started calculus. However most people use s.t rather than that.

4. Nov 2, 2007

cristo

Staff Emeritus
I think that if your professor does use that symbol, then it's very confusing. As Gib Z says, $\in$ means a member of and so the backward version means exactly the same: e.g. $\mathbb{N}\ni n$.

5. Nov 2, 2007

futurebird

Okay. I just wanted to know if anyone else had seen it. I don't find it that confusing... I wanted to know if this is what it looked like becuse my prof writes it in this odd way.

6. Nov 2, 2007

leon1127

The symbol for "such that" and epsilon has a bit difference. The symbol is larger. But I havent seen anything springer book using that symbol for such that.