I heard somewhere that '!' in maths is 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 *1 or something. And you can read 1! as 1BANG. I think. Is that true? If not, can someone explain this to me?

\(n!\) is read as '\(n\) factorial' or 'factorial \(n\)'.

If \(n\) is a non-negative integer, then

\[n!=1, \text{when}\ n=0\]

\[n!=n\times (n-1)!\ \text{when} \ n>1\]

In other words, if \(n\) is an integer greater than \(0\), then \(n!=n\times (n-1)\times (n-2)\times \cdots \times 2\times 1\). And \(0!=1\) by definition.

Easy Math Editor

`*italics*`

or`_italics_`

italics`**bold**`

or`__bold__`

boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

paragraph 2

`[example link](https://brilliant.org)`

`> This is a quote`

Remember to wrap math in \( ... \) or \[ ... \] to ensure proper formatting.`2 \times 3`

`2^{34}`

`a_{i-1}`

`\frac{2}{3}`

`\sqrt{2}`

`\sum_{i=1}^3`

`\sin \theta`

`\boxed{123}`

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TopNewest\(n!\) is read as '\(n\) factorial' or 'factorial \(n\)'.

If \(n\) is a non-negative integer, then

\[n!=1, \text{when}\ n=0\]

\[n!=n\times (n-1)!\ \text{when} \ n>1\]

In other words, if \(n\) is an integer greater than \(0\), then \(n!=n\times (n-1)\times (n-2)\times \cdots \times 2\times 1\). And \(0!=1\) by definition.

I hope this helps!

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