Hey, I just wached a video by D.r James Grime on YouTube about zero factorial and this popped up so I decided to try it on my own and saw that -1! was -1 but, isn't -1 factorial (!) "-1!= 0!/0=1/0≠-1" because it's divided by zero?
0/0 is undefined but it also is an "indeterminate expression", meaning that its value is determined by the problem that created this value. In one case, its value may be 0, in another case, its value may be 1, or -7 or pi/2, etc.
