Feb 19, 2015 · It's an abbreviation of quod erat demonstrandum, which is the Latin translation of a Greek phrase meaning "which had to be proven". To the ancient Greeks, a proof wasn't complete …

May 31, 2019 · QED is short for the Latin phrase quod erat demonstrandum and means, loosely, "that which was to be shown". As noted in the comments, it's a summary way of saying that the proof is …

Oct 26, 2022 · 1 In math, proofs are often accompanied by 'QED' (quod erat demonstrandum) at the end, indicating their conclusion. Some authors use a square symbol ($\square$) instead of QED, …

Apr 21, 2017 · 0 I had always used QED (quod erat demonstrandum) at the end of a proof until I was introduced to using Halmos' symbol. Since it was a 4-sided symbol, my mind has always associated …

It originates from the Greek: hóper édei deîxai (ὅπερ ἔδει δεῖξαι), meaning "which had to be demonstrated". So the Latin Q.E.D. is a variation on the translation of the the expression used by the …

Oct 21, 2016 · I already wondered about it some time ago: What is the difference between black and white square in notation? Now I found in Mathematical Logic for Computer Science by Mordechai …

Oct 7, 2014 · It's just a phrase, so it should be used where appropriate. One "makes" or "does" a construction, and "proves" or "demonstrates" a theorem. So, QEF when a construction is finished, …

Nov 20, 2011 · Many symbols in math don't have a single meaning; and in fact this is not quite mathematics, but rather the use of a symbol as a shorthand, among mathematicians, for what would …

Q.E.D. is an initialism of the Latin phrase quod erat demonstrandum, originating from the Greek analogous hóper édei deîxai (ὅπερ ἔδει δεῖξαι), meaning "which had to be demonstrated".

Dec 12, 2023 · Most propositions either end with "QED" or with "QEF", when the first one is used for proving propositions that are not constructions and the second one is for constructions. However, in …