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Factorial of 0=1 ?!
Can anyone please explain to me the proof that the factorial of 0 is 1?
Can anyone please explain to me the proof that the factorial of 0 is 1?
If you define (n+1)!=(n+1)*n!, 1!=1
JSuarez said:Please note that this function:
Is not defined for n = 0, so you can't really choose this...
JSuarez said:Please note that this function:
Is not defined for n = 0, so you can't really choose this...
The domain of a function is part of the definition of that function! You can't say "I define a function [itex]\mathbb{Z}\to \mathbb{Z}[/itex] by writing some formula, but hey, for negative integers the formula doesn't make sense, oh well".arildno said:Sure it is defined.
I defined a general function from the integers into itself.
Then, it is a matter of exploration to find out which subset of the integers that can properly be regarded as the argument set. (The negatives are seen to be ruled out).
then you have specified the "base case" to be n=1. There has to be a base case (the formula (n+1)!=(n+1)*n alone does not make sense as definition), and it is part of the definition.(n+1)!=(n+1)*n!, 1!=1
is well-defined if and only if 0!=1.[tex]!:\mathbb{N}\cup\{0\}\to \mathbb{N}\cup\{0\}[/tex]
defined by 1!=1 and, for all [itex]n\in\mathbb{N}\cup\{0\}[/itex], (n+1)!=(n+1)*n!
CompuChip said:That's a bit of an oversimplification blob.
Is (-1)! = 0!/0 = 1/0 then?
CompuChip said:That's a bit of an oversimplification blob.
Is (-1)! = 0!/0 = 1/0 then?
Gamma(-1) is a projective complex number; it doesn't "tend", it simply is projective infinity.Char. Limit said:Actually, if you look at the gamma function, [itex]\Gamma\left(-1\right)[/itex] does tend to infinity
The factorial of 0 is defined as 1. This means that 0! = 1. It is a special case in factorial calculations and is often a point of confusion.
The factorial of a number is defined as the product of all positive integers from 1 up to that number. In the case of 0!, there are no positive integers to multiply, so the product is 1. This is a mathematical convention and is important in certain calculations.
Yes, the factorial of 0 is used in various fields such as statistics, probability, and combinatorics. It is also used in computer science algorithms and in the calculation of binomial coefficients.
Yes, the factorial of 0 can be proven using mathematical induction. It can also be proven using the definition of factorial and by showing that it follows the same pattern as other factorials.
No, the factorial of 0 is not the only number equal to 1. In fact, any number raised to the power of 0 is equal to 1. This is another mathematical convention and is useful in various calculations and proofs.