where is the factorial (!) on a TI-83?

Question

Thanks! in advance

Answer 1

Punch math. Go right to PRB; short for probability.

Answer 2

It depends on how advanced you want to get. There is a function called
the Gamma Function defined in various ways:

For x>0, Gamma(x)=Integral{x=0 to infinity} t^x-1 e^-t dt

This function has a property called the Factorial property, namely
that Gamma(x+1)=xGamma(x). By rewriting the factorial property as
Gamma(x)=1/x Gamma(x+1) you can actually define the Gamma Function for
x<0 [[if -1 Now if -2 etc.]]

The function can also be defined as

Gamma(x)=e^(-bz) Product{n=1 to infinity} (1+z/n)^-1 e^(z/n)
(where b makes Gamma(1)=1)

or as

lim{n->infinity} n!n^(z+1)/[z(z+1)...(z+n)]

Note that Gamma(n+1)=n! (let z=1 in the Factorial property), so the
Gamma function generalizes the factorial function.

The fact that all the defintions are equivalent on their domains and
that the factorial property holds are not easy!

With the definition(s), Gamma(1/2)=Sqrt[Pi], which may explain why the
TI-83 uses the definition it does. For those without a TI-83 manual
the definition is

(n+1)!=n*n! recursively until n=0 or -1/2 and then 0!=1 and (-1/2)!=
Sqrt[Pi]

n!=n(n-1)(n-2)...2.1 if n>0 and an integer

n!=n(n-1)(n-2)...2.1 .Sqrt[Pi] if n+1/2 >0 and an integer.

You can find information in most books on complex variables/analysis
or in books about "advanced engineering mathematics".

Answer 3

Click Math right under the Alpha, then click over to the right until the PRB is highlighted, click 4 and you will get your factorial

Answer 4

On my calculator I look for n!. It is above one of the numbers 1 , 2, or 3.

Answer 5

I have a TI-85 and it's under
2nd MATH >> PROB >> !

Answer 6

It's been a while since I used one, but it had an x! button. You have to use one of the shift or function keys to get to it.

Answer 7

green diamond and divided by symbol

Answer 8

Perhaps this link will help??