Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

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## #1 2007-11-06 02:27:36

ganesh
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### Symbols

Hebrew letter Aleph, Used in Mathematics, Number Theory, as in Aleph Null

Partial, pronounced doe

Greek letter Delta, Triangle in Geometry

Infinity

Greek letter Sigma, Sum, Summation

Union, in Set theory

Intersection, in Set theory

Subset, in Set Theory

Superset, In Set Theory

Parallel

Perpendicular

Approximately

Congruence

Proportional to

Belongs to, in Set theory

Less than or equal to

Greater than or equal to

Not equal to

Not approximately

Plus or minus

Empty set, containing no elements

Character is who you are when no one is looking.

## #2 2007-11-06 03:45:37

ganesh
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### Re: Symbols

Pi, Greek alphabet, denoting the ratio of circumference of a circle to its diameter. Approximately 22/7. Approximately 3.14

Delta, Greek alphabet, denoting a small quantity

Vector a

Unit vector a

Character is who you are when no one is looking.

## #3 2007-11-06 16:36:43

ganesh
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### Re: Symbols

= Alpha, Greek Alphabet, In Physics (Mechanics), denotes acceleration

= Omega, Greek Alphabet, In Physics (Mechanics), denotes angular velocity

= Beta, Greek alphabet, In atomics physics, denotes a type of particles, Beta particles.

= Gamma, Greek Alphabet, In atomic and nuclear physics, denotes a kind of rays, Gamma rays.

Character is who you are when no one is looking.

## #4 2007-11-06 17:04:47

ganesh
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### Re: Symbols

= Greek letter, Tau, in Physics, Mechanics, Torque.

= Greek letter, mu, in Physics, in Electiricty and Magnetism, Permeability.

= Greek letter, nu, in Physics, Optics, Refractive Index

= Greek letter, eta, in Physics, used to denote coefficient of Viscosity in Hydrodynamics, Hydostatics

= Greek letter, Sigma, lower case, in Physics

= Greek letter, Omega, upper case

Character is who you are when no one is looking.

## #5 2007-11-06 17:48:28

ganesh
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### Re: Symbols

= Root, if no number other than 2 is put inside the symbol, Square root

= Power of, usually. This is not a universal code in mathematics though.

= Tetration, in number theory in Mathematics. As in Knuth's up-arrow notation.

Character is who you are when no one is looking.

## #6 2007-11-07 23:33:45

Identity
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### Re: Symbols

Do you know what this symbol is? I remember seeing it somewhere, but I don't know what it means. You can delete my post after.

## #7 2007-11-08 00:48:29

mathsyperson
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### Re: Symbols

I believe that that's used in sets.
If

, then there's an injection from B to A.

Why did the vector cross the road?
It wanted to be normal.

## #8 2007-11-11 02:13:45

ganesh
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### Re: Symbols

= Angle

= Negation, in Symbolic logic

= And, in symbolic logic

= Or, in Symbolic logic

Last edited by MathsIsFun (2008-11-03 07:16:16)

Character is who you are when no one is looking.

## #9 2007-12-16 22:07:49

ganesh
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### Re: Symbols

Up arrow as in Donald Knuth's up arrow notation.

Up arrow as in Donald Knuth's up arrow notation.

Chained arrow as in John Conway's chained arrow notation.

Character is who you are when no one is looking.

## #10 2007-12-17 04:35:28

Ricky
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### Re: Symbols

: Tensor product
: Direct sum
: Direct product

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

## #11 2007-12-28 02:16:01

ganesh
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### Re: Symbols

: Contains as a member

: Not an element of

: much less than

: much greater than

: congruent to

: asymptotic

: not equal to

: not less than

: not greater than

: not less than or equal to

: not greater than or equal to

: not subset

: not superset

: not similar

: not congruent

: not approximately equal to

: not asymptotic

Last edited by MathsIsFun (2008-11-03 07:19:50)

Character is who you are when no one is looking.

## #12 2008-03-12 08:34:21

Daniel123
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### Re: Symbols

I came across this symbol today as a subscript to L, and it meant luminosity using the sun's as a base - so I'm guessing it means "using the stated base".

## #13 2008-11-02 16:18:25

All_Is_Number
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### Re: Symbols

#### ganesh wrote:

= And, in symbolic logic

= Or, in Symbolic logic

I believe those are reversed.

= Or (corresponding to
)

and

= And (corresponding to
)

You can shear a sheep many times but skin him only once.

## #14 2008-11-02 16:28:03

All_Is_Number
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### Re: Symbols

#### ganesh wrote:

: Does not belong to, in set theory

: Contains as a member

: Not an element of

You can shear a sheep many times but skin him only once.

## #15 2008-11-02 22:57:55

MathsIsFun

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### Re: Symbols

All_Is_Number: I think you are right ... does anyone else concur/disagree?

If we get agreement I can simply edit the original post

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

## #16 2008-11-02 23:32:23

mathsyperson
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### Re: Symbols

Yes, I'd agree with those.
Maybe people started getting abusive and it got deleted?
(Or maybe I made it all up )

Why did the vector cross the road?
It wanted to be normal.

## #17 2008-11-03 00:29:26

integer
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### Re: Symbols

How are the symbols accessed?
How can I generate/create a symbol?

## #18 2008-11-03 01:11:00

mathsyperson
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### Re: Symbols

The symbols are part of the LaTeX language that can be used on this forum.
You can post LaTeX by using $tags. As a random example, [math]\sin(\pi)=0$ becomes

.

There's a fairly thorough tutorial on LaTeX stickied in Help Me!. You can also click on any LaTeX image (like all the ones in the posts above) to see the code that made it.

Why did the vector cross the road?
It wanted to be normal.

## #19 2008-11-03 07:21:03

MathsIsFun

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### Re: Symbols

Fixed both, thanks All_Is_Number and mathsy

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman