...........recall the maths ones when doing 'O' levels aeons ago.

Any whole number divided by itself = 1

so 1/1 = 1

& 0/0 = 1

infinity/infinity = 1

Also indices or 'powers' of numbers,

any number raised to power 0 = 1

so a billion squillion to power/index 0 = 1

& 0 to power 0 = 1

Division:

any number divided by 0 = infinity

1/0 = infinity


Zero divided by anything = 0

except 0/0 = 1