The Sturm sequence is printed and evaluated at x = b.
The number V(b) of sign-changes in the evaluated sequence is also printed.
(Sturm's theorem states that if a < b and f(a)f(b) ≠ 0, then V(a) – V(b) is the number of reals roots of f(x) in the open interval (a,b).
See A.G. Akritas, Elements of computer algebra with applications, p. 341 and N. Jacobson, Basic Algebra I, p. 298.)
Last modified 20th July 2006
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