Zero Factorial is One?

[Misodoctakleidi]

When i type out 0! on my calculater it gives an answer of 1, does anyone know why that is?

I would have expected it to be 0

[psi20]

There's this cool pattern.

Say you had a pattern of squares.
1^2 2^2 3^2
1 4 9
3 5
2

You subtract the previous term to the next term in the series.

Say you had cubes
1^3 2^3 3^3 4^4
1 8 27 64
7 19 37
12 18
6

Say you had firsts.
1^1 2^1
1 2
1

Say you had zeroeths
1^0
1

You only need one term more than the exponent. The difference is going to be the factorial of the number. I've never tried negatives yet.

[Neurocomp2003]

well do you know what the factorial stands for?

its the number of arrangements of a set of distinct objects.
Now then 1 and 0 are the foundations of factorial like they are in the number system.

so 1! is the arrangement of 1 object which is one.
then 0! is the arrangement of 0 objects ...since there are no objects to arrrange the answer is also one.

[ski_power]

Oh ok, now I got it. But then whenever I try factorial of a negative number it says error. Can anyone please explain this?

[dave]

If you think about it, how can you have the arrangement of -1 objects? It just doesn't make sense.

The factorial function can be extended to cover the entire set of real and complex numbers, and it is called the gamma function. If you're interested in it, you can find more details here (http://mathworld.wolfram.com/GammaFunction.html).

[YT2095]

When i type out 0! on my calculater it gives an answer of 1, does anyone know why that is?

I would have expected it to be 0

is the 0 key next to the 1 key? it`s quite possible the keypad membrane is sticky or there is a metalic dust on the 0 Keys tracks adjacent to the 1 keys tracks causing a short, as the keypads are often constructed out of a single peice of material, rubber or plastic.
an Air hose or carefull dismanteling and cleaning with a damp cloth (no solvents) may fix this for you :)

[dave]

is the 0 key next to the 1 key? it`s quite possible the keypad membrane is sticky or there is a metalic dust on the 0 Keys tracks adjacent to the 1 keys tracks causing a short, as the keypads are often constructed out of a single peice of material, rubber or plastic.
an Air hose or carefull dismanteling and cleaning with a damp cloth (no solvents) may fix this for you :)

0! is defined 1, no doubt about it :-)

[bloodhound]

I WAS about to say the same thing dave. totally agree with u theeere