radical

The   $\sqrt{}$  is called a radical. The of the radical symbol is the first letter “r” of the Latin radix, which “root (http://planetmath.org/NthRoot)”.

There is other terminology that is related to radicals: In the expression $\sqrt[3]{x}$, $x$ is the radicand and $3$ is the index.

The index of a radical is usually an integer at least as large as two; however, if the index is two, it is usually not written. Moreover, if a radical does not have a written index, it is understood to be two, in which case the radical denotes a square root.

A radical expression is an expression that involves a radical.

One can use fractional powers instead of the radical symbol via $\sqrt[n]{x}=x^{\frac{1}{n}}$. This practice of avoiding the radical symbol may be due to typesetting issues.

Title	radical
Canonical name	Radical12
Date of creation	2013-03-22 17:06:00
Last modified on	2013-03-22 17:06:00
Owner	Wkbj79 (1863)
Last modified by	Wkbj79 (1863)
Numerical id	22
Author	Wkbj79 (1863)
Entry type	Definition
Classification	msc 30-00
Classification	msc 12D99
Classification	msc 00A05
Synonym	radical symbol
Related topic	Radical5
Related topic	EvenEvenOddRule
Related topic	NthRoot
Defines	radicand
Defines	index
Defines	radical expression