The formula with the obelus is merely tabulated by Rahn with no text, and if the motivation was known, Cajori would have mentioned it in History Of Mathematical Notations, which is a classical treatise. It is likely that Rahn (or Pell) simply repurposed the minus sign symbol, it was used from Riese's algebra textbook (1525) onward.

"Radical" comes from Latin "radicalis", having roots, an equivalent "radix" was also commonly used earlier. While Rudolff did use the radix in 1525 his did not have the overbar on top, now called vinculum, Latin for

See Forian Cajori, A History of Mathematical Notations (1928, also Dover reprint), Vol.II, page 61:. 438.The sign $\Sigma$ for summation is due to Leonhard Euler ...

2015年6月15日 · In a book, I saw a short anecdote about something called the "Horus-eye" hieroglyph, supposedly used in parts to represent fractions (the book dates to 1997). Wikipedia has an article on the symbol...

Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

2023年11月5日 · I’ve noticed a recurring post on social media that presents an image suggesting the shapes of Hindu-Arabic numerals are connected to the angles within their design: This claim seems dubious to me....

2016年6月1日 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

2019年1月7日 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

2019年8月3日 · The J symbol can represent the unit of energy but it's also the symbol for the dimension of the candela (or luminous intensity). For the energy unit, it clearly comes from the family name of the E...