Re:U+237C ⍼ Right Angle with Downwards Zigzag Arrow
by AaronFriel on Wednesday April 13, 2022 @02:32PM
(#31018412)
Math degree holder from Iowa, yeah, I've seen and used it many times. The symbol is used when you reach the contradictory statement. Like "1 = 2".
"By way of contradiction suppose P, then ..., thus ~P ↯. Therefore ..."
Re:U+237C ⍼ Right Angle with Downwards Zigzag Arrow
by nerdponx on Wednesday April 13, 2022 @07:38PM
(#31021670)
I've actually always wanted a way to mark "the contradiction" once I've obtained it. Thanks!
Re:U+237C ⍼ Right Angle with Downwards Zigzag Arrow
by phogster on Wednesday April 13, 2022 @07:22PM
(#31021540)
To me that reads: I throw your assumption into the GROUND!
Re:U+237C ⍼ Right Angle with Downwards Zigzag Arrow
by valtism on Wednesday April 13, 2022 @05:58PM
(#31020815)
I was taught it in extracurricular mathematics in Australia. We were taught that it goes at the end of a contradiction proof once the contradiction has been found. We used to write it extra large, like lightning strike. I think of it like a proof mic-drop.
And some commenters said they used it to mark proof by contradiction, but why is there a need to mark it when you are showing it via proof? A canonical example of proof by contradiction is proving sqrt(2) is not rational. Never have I seen it marked with that symbol. Where would you even mark it? At the beginning with the assumption? Or at the end like QED?