Count sign changes to estimate the possible number of positive and negative real roots.
Last updated: June 2026 | By Patchworkr Team
Use `^` for exponents. Invalid terms are rejected.
The number of positive real roots is the count of sign changes in P(x), or less than that by an even number.
For negative roots, apply the same idea to P(-x). Zero coefficients are ignored when counting sign changes.
This example has 4 sign changes for positive roots and 0 sign changes for negative roots.
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