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→This is really a usage question
:After struggling through some of the math coding, I think I have clarified the article by defining the radical symbol as the principal square root only, while making it more clear that there are two square roots.
:After struggling through some of the math coding, I think I have clarified the article by defining the radical symbol as the principal square root only, while making it more clear that there are two square roots.
Another usage data point, although biased by the fact that I searched for the phrase "principal square root." And, darn it all, it points out that not every number has two square roots: the exception is 0.
:All positive numbers have two square roots, one positive, one negative. The two square roots of 9 are 3 and -3, and the two square roots of 144 are 12 and -12. The number 0 is the only number that has one square root, which is zero. The '''principal square root''' of a positive number is its positive square root.... The symbol √, which is called a '''radical symbol,''' is used to represent the the principal square root of a number, and -√ is used to represent the negative square root of a number.
::Gustafson, R. David and Alan S. Tussy (2006) ''Introductory Algebra,'' Thomson Brooks/Coles, [http://books.google.com/books?id=8iHLN8eXuUwC&pg=PA565&ots=gCTZiHg9yo&dq=%22principal+square+root%22&sig=90fhwp5PYuHtepVC-e59D0G97Zk p. 565]. [[User:Dpbsmith|Dpbsmith]] 18:10, 24 April 2007 (EDT)
==Generalisation==
==Generalisation==