Saturday

December 20, 2014

December 20, 2014

Posted by **tiffanie robinson** on Wednesday, August 31, 2005 at 6:00pm.

I assume you know what a factorial is:

1! = 1

2! = 1x2 = 2

3! = 1x2x3 = 6

N! = 1x2x3x...x(N-1)xN

They occur often in probability theory.

Please ask a more specific question about factorials. I have no idea what else to tell you.

what is the explicit formula for the nth factorial? is there one without n*(n-1)*(n-2) and so forth?

No, drwls is correct; N! = 1*2*3...*N.

However, when using factorials, short-cuts and simplifications will often be present. For example, the formula for counting the number of ways one can deal two cards from a standard 52-card deck is:

52! / 2!(52-2)!

Well, calculating 52! by itself is an onerous task. However, we can simplify. 52!/50! cancels to 51*52, and 2! is simply 1*2=2. So, the answer is 51*52/2 = 1326.

I hope this helps

Why is 0! equal to one? write back asap!!

-concerned student seeking help

**Answer this Question**

**Related Questions**

math - what is the factorial of a negative number? The factorial function has ...

Algebra (factorial) - Evaluate gcd(19!+19,20!+19). Details and assumptions The ...

math - Find the sum of all positive integers m such that 2^m can be expressed as...

math - Simplify: 2/1! - 3/2! + 4/3! - 5/4! + ... + 2010/2009! - 2011/2010!, ...

Algebra 1 - Can you please check my work and help me with the parts that I don't...

math - WAT IS 12 FACTORIAL

math - Evaluate the factorial. 5!

math - what is expression 5 factorial equal

precalculus - Simplify the Factorial Expression. (3n+1)!*3!/(3n-2)!

math - I know that (n+1)! = n!(n+1) but how would i solve the factorial: (2n+3...