Descartes' rule of signs


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Descartes' rule of signs

[dā′kärts ′rül əv ′sīnz]
(mathematics)
A polynomial with real coefficients has at most k real positive roots, where k is the number of sign changes in the polynomial.
References in periodicals archive ?
More specifically, the paper demonstrates the applicability of Descartes' Rule of Signs, Budan's Theorem, and Sturm's Theorem from the theory of equations and rules developed in the business literature by Teichroew, Robichek, and Montalbano (1965a, 1965b), Mao (1969), Jean (1968, 1969), and Pratt and Hammond (1979).
Of particular interest are Descartes' Rule of Signs, Budan's Theorem, and Sturm's Theorem from the theory of equations, and the rules developed in the business literature by Teichroew, Robichek, and Montalbano (1965a, 1965b), Mao (1969), Jean (1968, 1969), and Pratt and Hammond (1979).
In addition, Descartes' Rule of Signs is actually a special case of Budan's Theorem, which will be discussed next.
Descartes' Rule of Signs indicated that there are no more than two, and possibly no positive solutions.