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The number of real roots of a bivariate polynomial on a line

Martin Avendano
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Abstract

We prove that a bivariate polynomial f with exactly t non-zero terms, restricted to a real line {y=ax+b}, either has at most 6t-4 zeroes or vanishes over the whole line. As a consequence, we derive an alternative algorithm to decide whether a linear polynomial divides a bivariate polynomial (with exactly t non-zero terms) over a real number field K within [ log(H(f)H(a)H(b)) [K:Q}] log(deg(f)) t]^{O(1)} bit operations.

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Martin Avendano. 2007-02-28. The number of real roots of a bivariate polynomial on a line. https://arxiv.org/abs/math/0702891

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