I was wondering about this.Please help
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I was wondering about this.Please help
Technically, no. However, there is something called the Gamma function which is an extension of the factorial function.
See: Gamma function - Wikipedia, the free encyclopedia
Technically there is.
There is such a thing as .5!
Since (x-1)! = x!/x
(-.5)! = (.5)!/.5 = 2 * (.5)!
However, anything less than -.5 has no factorial as it'd be dividing by 0.
i.e. -1! = 0!/0 = 1/0
-2! = -(1/0) /0
I didn't even know about decimal factorials, but I tried it with my calculator and it found that .5 factorial was valid, so I tried -.5 factorial and it worked too.
Likely you're calculator is actually computing the gamma function. The gamma function exists for all complex numbers except non-negative integers.
It's been roughly defined as (n-1)!, though the true definition is an improper integral (see the wikipedia article).
The definition of the classical factorial function only exists for positive real numbers, with a special exception that 0! = 1.