Explained two Negative numbers makes positive numbers

Same principle goes for why taking a number to the zeroth power = 1
10^3=1000
10^2=100
10^1=10
10^0=?

— Dmitri Petrov (@PetrovADmitri) June 24, 2019

I've always liked

n! = n*(n-1)!

So

(n-1)! = n!/n

And so it must be that

0! = 1!/1 = 1

— Phillip Compeau (@PhillipCompeau) June 24, 2019

http://mathisvisual.com/
https://mathsedideas.blogspot.com/p/resources.html#RAMs