Answer:
That is math definition
Explanation:
However, sometimes you can write
0 divide 0 and there actually is a exist answer，when 0 isn't pure 0→in effect,it's ever close to 0 but not 0
for example：sinx/x=?
when x is close to 0, sinx close 0,too
so the answer is 1
if you are interested in it ,you can learn
"limit" on any University site