Who Invented the Square Root?

Date: 12/11/96 at 00:40:34
From: Mason
Subject: Square root

Dr. Math,

Who invented the square root?  I mean, I've only seen long, stringy 
roots!

Mason

Date: 12/11/96 at 11:26:20
From: Doctor Rob
Subject: Re: Square root

I assume you mean who first used the phrase "square root" to refer 
to a number which when multiplied by itself produces a given number.
  
The "square" part comes from the equation x^2 = 16 (or x^2 equals any 
given number).  The word form of the equation is "x squared equals 
sixteen".  Prior to that it seems to have come from the formula for 
the area of a square with side length x:  A = x^2 = x*x.  

The "root" part is the translation of the Latin word "radix" which was 
used during the Renaissance by mathematicians who wrote all their 
mathematics in Latin.  I am not sure who first used this, but it was 
surely in use by the time of Pierre de Fermat in the 1630's.

-Doctor Rob,  The Math Forum
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