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.

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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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