# 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 |