QED = QED) is an initialism of the Latin phrase quod erat demonstrandum, meaning "what was to be demonstrated," or without Latin borrowings, "what was to be shown."
This phrase may be written at the end of a complicated mathematical or scientific answer to show that you believe you have correctly demonstrated that your answer is proved.
QED = QEDは、ラテン語のquod erat demonstrandumの頭文字をとった、「こう証明された」という意味の言葉です。
これは難しい数学の証明や科学的な回答の最後に、自分の答えの証明を正しく説明したであろうと示すために書かれます。
証明終了はQEDで事足りますが、
2つめのように、
...であると言える十分な証拠がある。
といった言い方も前につけたりします。
From (1) and (2),
There is enough evidence to conclude that the triangle ABC is bigger than the triangle DEF. QED.
(1),(2)より、三角形ABCは三角形DEFより大きいと言える十分な証拠がある。証明終了。
quod erat demonstrandum
"Q.E.D." (sometimes written "QED") is an abbreviation for the Latin phrase "quod erat demonstrandum" ("that which was to be demonstrated"), a notation which is often placed at the end of a mathematical proof to indicate its completion.
quod erat demonstrandum
"Q.E.D." (sometimes written "QED") は、ラテン語の"quod erat demonstrandum" ("証明されたもの")の短縮形で、これは、数学の証明で証明終了を表す言葉として最後に置かれます。
QED is short for a latin phrase: Quod erat demonstrandum...Here it is shown!
QED. What was to be demonstrated" or "what was to be shown." IE the proof.
Quod erat demonstrandum...is now shortened to QED and is commonly placed after statements as a stamp of conclusive proof being shown;-D
「Quod Erat Demonstrandum」は「what was to be demonstrated/what was to be shown（証明されるべきこと）」という意味です。つまり「proof（証明）」です
「Quod Erat Demonstrandum」は「QED」と短縮され、証明が終わった証として最後に置かれます。
QED stands for quod erat demonstrandum. It is a Latin phrase. It is used at the end of a mathematical problem to indicate its completion.
QED は Quod Erant Demonstrandum の頭文字です。ラテン語のフレーズで、証明し終わった状態を示すために、数学の問題の最後に置かれます。
Quod Erant Demonstrandum の直訳は「それは証明されるべきだった」で、「今では証明されている」ということを意味しています。
QED is commonly written in English which stands for the latin phrase "Quod Erat Demonstrandum", which is Latin for "that which was to be demonstrated". It is also common to draw a square or rectangle known as a tombstone. In spoken English you would say "which was to be shown" when presenting a paper orally.
英語では「QED」と書くことが多いです。これはラテン語の「Quod Erat Demonstrandum (=that which was to be demonstrated)」の略です。
また「tombstone (墓石)」という正方形または長方形の記号を書くのも一般的です。
口頭で発表する時には「which was to be shown」と言うと思います。
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