Why does the square root symbol look like it does?

Answer by  Clement (1453)

The square root sign originates from the Christoph Rudolff's Die Coss published in 1525. The sign is an alteration of the letter "r", from "radix" - root in Latin. Rudolff's sign did not use the vinculum, so in its original form the similarity with "r" is quite close. Vinculum was added by Rene Descartes in 1637.

Answer by  eccentricoz (107)

The square root symbol, better known as a radical, is deceptively similar to a long division symbol. The only exception is that the radical has an extra line which makes its left side look like a check mark. It isn't a Greek letter at all, which is why it doesn't look like one.