Professor Raúl Rojas has published a book about how symbols have been used throughout history in mathematics. The work was translated into English this year.

The @ symbol can also appear in regular formulas outside of tables when Excel thinks you're trying to reference a single value from a range. If you see it pop up unexpectedly, it usually means Excel ...

The Wisteria Table Lamp (Clara Driscoll - Tiffany Studios, c.1905) has a cylindrical shade topped by a dome, so it is a geometric form. But the bottom of the shade has an irregular edge representing ...

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