# Difference between revisions of "Iff"

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'''Iff''' is an abbreviation for the phrase "if and only if." | '''Iff''' is an abbreviation for the phrase "if and only if." | ||

+ | In mathematical notation, "iff" is expressed as <math>\iff</math>. | ||

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+ | If a statement is an "iff" statement, then it is a [[conditional|biconditional]] statement. | ||

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+ | ==Example== | ||

In order to prove a statement of the form, "<math>p</math> iff <math>q</math>," it is necessary to prove two distinct implications: | In order to prove a statement of the form, "<math>p</math> iff <math>q</math>," it is necessary to prove two distinct implications: | ||

* <math>p</math> implies <math>q</math> ("if <math>p</math>, then <math>q</math>") | * <math>p</math> implies <math>q</math> ("if <math>p</math>, then <math>q</math>") | ||

* <math>q</math> implies <math>p</math> ("if <math>q</math>, then <math>p</math>") | * <math>q</math> implies <math>p</math> ("if <math>q</math>, then <math>p</math>") | ||

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==See Also== | ==See Also== |

## Revision as of 12:35, 26 January 2013

**Iff** is an abbreviation for the phrase "if and only if."

In mathematical notation, "iff" is expressed as .

If a statement is an "iff" statement, then it is a biconditional statement.

## Example

In order to prove a statement of the form, " iff ," it is necessary to prove two distinct implications:

- implies ("if , then ")
- implies ("if , then ")

## See Also

*This article is a stub. Help us out by expanding it.*