/sci/ - Science & Math

>>12520995
Thanks. I think that looks correct, which is quite sad. I hope you don't mind if I borrow your solution in a paper of mine. An immediate corollary is that H is subgroup iff it satisfies the conditions of being a subgroup.

>>11750553
I know that feel. It's funny how it starts growing in the beginning when you make arguments in the end and then it hits you: I DID NOT PROVE THIS FACT! Then you try to prove it, things go smoothly and your argument, that clever little trick you wrote smiling, was not proved before. Care to share an example of something you are uncertain whether to prove or not?
PS. If you are under 24 years, you don't have my permission to die.