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### Math Symbols

```
Date: 04/07/97 at 22:22:36
From: Bob Howell
Subject: Math Symbols

I do not know what many of the math symbols in my book mean (like the
upside down A, backward E, etc., etc.) Where can I find definitions
of these symbols?  Thanks for your help.

Bob Howell
```

```
Date: 04/08/97 at 21:35:35
From: Doctor Keith
Subject: Re: Math Symbols

Hi,

Most math books put an appendix with notation or mention it in the
preface, to avoid this problem.  Here are a couple of basics:

1. upside down A  means  "for all"

2. backward E    means  "there exists"

3. epsilon (looks like c with horizontal line in middle)
means  "an element of" or "in" of "belongs to"

4. backwards epsilon
means  "such that"

5. three dots triangle, point up
means  "therefore" or "thus"

6. three dots triangle, point down
means  "because" or "due to"

These basic four cover most of the cases that you will find but of
course many others exist.  You can always go to a library and check
out a book by another author, who includes the symbol definitions.

There's also a link to the page that compiles information about the
first uses of some math symbols at the bottom of our Dr. Math FAQ:

http://mathforum.org/dr.math/faq/

-Doctor Keith,  The Math Forum
Check out our web site!  http://mathforum.org/dr.math/
```
Associated Topics:
College Definitions
College Logic