YAM(ath)T: What does that sign mean?

[ndee]

OK, I started studying and the teacher gave us some very basic math stuff. The problem is, I don't know what following sign means: http://www.duderinos.ch/math.jpg

Any help is appreciated!

 

[Aves]

I think it means they didn't have the required font on their computer! 😛

 

[imported_Pablo]

looks like one of the default characters that a font uses when it can't find the right character...

(i confuse myself...)

 

[ndee]

Originally posted by: aves2k
I think it means they didn't have the required font on their computer! 😛

That was my first thought but how can I be sure?

 

[FoBoT]

a rectangle? i dunno

 

[Tauren]

It just couldn't find the appropriate font so it inserted a space holder.

 

[iamme]

Originally posted by: aves2k
I think it means they didn't have the required font on their computer! 😛

lol, that's what i was thinking 🙂

 

[sciencewhiz]

Originally posted by: ndee

Originally posted by: aves2k
I think it means they didn't have the required font on their computer! 😛

That was my first thought but how can I be sure?

ask the teacher?

 

[chuckywang]

Yeah, it's definitely not rendered right. Hmm...my guess at what it is supposed to be is Z+, the positive integers.

 

[Brian23]

No, a,b, and c are elements of the square set!

 

[wfbberzerker]

its the box operator.

 

[Kyteland]

Originally posted by: ndee

Originally posted by: aves2k
I think it means they didn't have the required font on their computer! 😛

That was my first thought but how can I be sure?

For that equation to make any sense that symbol should either be Z R or N with a double linethrough it. Such as on these pages:
http://mathworld.wolfram.com/RealNumber.html
http://mathworld.wolfram.com/PositiveInteger.html


Edit: Oh, and there is no standard math operator that looks like that AFAIK.

 

[ndee]

Originally posted by: chuckywang
Yeah, it's definitely not rendered right. Hmm...my guess at what it is supposed to be is Z+, the positive integers.

after 10 pages, I think I figured it out it's all the "natural" numbers, that's what we call it in German.

 

[TuxDave]

So what are you trying to prove. Fermat's Last Theorem?

 

[chuckywang]

It's already been proven. 🙂

 

[silverpig]

Originally posted by: Kyteland

Originally posted by: ndee

Originally posted by: aves2k
I think it means they didn't have the required font on their computer! 😛

That was my first thought but how can I be sure?

For that equation to make any sense that symbol should either be Z R or N with a double linethrough it. Such as on these pages:
http://mathworld.wolfram.com/RealNumber.html
http://mathworld.wolfram.com/PositiveInteger.html


Edit: Oh, and there is no standard math operator that looks like that AFAIK.

Actually there is. The box (actually box^2) is d'Alembertian. It's sort of the 4-d analogue to the Laplacian.

Laplacian = upside down triangle^2 = (d/dx)^2 + (d/dy)^2 + (d/dz)^2
d'Alembertian = box^2 = -(d/dt)^2 + (d/dx)^2 + (d/dy)^2 + (d/dz)^2

Mathworld

 

[Kyteland]

Originally posted by: silverpig
Actually there is. The box (actually box^2) is d'Alembertian. It's sort of the 4-d analogue to the Laplacian.

Laplacian = upside down triangle^2 = (d/dx)^2 + (d/dy)^2 + (d/dz)^2
d'Alembertian = box^2 = -(d/dt)^2 + (d/dx)^2 + (d/dy)^2 + (d/dz)^2

Mathworld

That's more of a square than a rectangle....

</orneryBastard>

😉

 

[Modeps]

1=.9999999...