Why the Chi-square cannot be less than or equal to 1 ?

Dason

Ambassador to the humans
#2
It can. Are you referring to a specific test or something? Where did you "learn"that it can't be less than 1?
 

Dason

Ambassador to the humans
#4
It's definitely possible...

You should provide more detail. It seems you're operating under the assumption that the chisquare is only used for one purpose of which you're familiar with. That isn't the case. So please describe how you know it to be used.