Search results
Results From The WOW.Com Content Network
If this definition is used, the cube root of a negative number is a negative number. The three cube roots of 1. If x and y are allowed to be complex, then there are three solutions (if x is non-zero) and so x has three cube roots. A real number has one real cube root and two further cube roots which form a complex conjugate pair.
The two square roots of a negative number are both imaginary numbers, and the square root symbol refers to the principal square root, the one with a positive imaginary part. For the definition of the principal square root of other complex numbers, see Square root § Principal square root of a complex number.
A root of degree 2 is called a square root and a root of degree 3, a cube root. Roots of higher degree are referred by using ordinal numbers, as in fourth root, twentieth root, etc. The computation of an n th root is a root extraction. For example, 3 is a square root of 9, since 3 2 = 9, and −3 is also a square root of 9, since (−3) 2 = 9.
Then let =, where the symbols and are interpreted as any square root and any cube root, respectively (every nonzero complex number has two square roots and three cubic roots). The sign " ± " before the square root is either " + " or " – "; the choice is almost arbitrary, and changing it amounts to choosing a different square root.
The Egyptian mathematician Abū Kāmil Shujā ibn Aslam (c. 850–930) was the first to accept irrational numbers as solutions to quadratic equations, or as coefficients in an equation (often in the form of square roots, cube roots, and fourth roots). [10]
greek beta symbol u+03d1: ϑ: greek theta symbol u+03d2: ϒ: greek upsilon with hook symbol u+03d5: ϕ: greek phi symbol u+03f0: ϰ: greek kappa symbol u+03f1: ϱ: greek rho symbol u+03f4: ϴ: greek capital theta symbol u+03f5: ϵ: greek lunate epsilon symbol u+03f6 ϶ greek reversed lunate epsilon symbol
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
In the case of three real roots, the square root expression is an imaginary number; here any real root is expressed by defining the first cube root to be any specific complex cube root of the complex radicand, and by defining the second cube root to be the complex conjugate of the first one.