In algebra, a **Bring radical** or **ultraradical** of a complex number *a* is a root of the polynomial

(The root is chosen so the radical of a real number is real, and the radical is a differentiable function of *a* in the complex plane, with a branch cut along the negative real line below −1. See the "Bring radicals" section below.)

George Jerrard (1804–1863) showed that some quintic equations can be solved using radicals and Bring radicals, which had been introduced by Erland Bring (1736–1798). They can be used to obtain closed-form solutions of quintic equations.

Read more about Bring Radical: Normal Forms, Series Representation, Solution of The General Quintic, Other Characterizations

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