Enter coefficients from highest to lowest degree, separated by spaces or commas.
Rational, irrational and complex roots + full factorization.
Every synthetic division pass, explained.
Real roots marked on the x-axis.
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The Remainder Theorem states that evaluating $P(a)$ gives the exact remainder $R$ when $P(x)$ is divided by $(x - a)$.
Compare substitution directly against synthetic division (Ruffini).
A polynomial $P(x)$ has a factor $(x - a)$ if and only if $P(a) = 0$.
Is $(x - a)$ a factor of $P(x)$?
Find all possible divisors $p$ (constant term) and $q$ (leading coefficient).
Click any $\pm(p/q)$ candidate to check if $P(r) = 0$.
Define desired roots and construct the expanded polynomial.
Simplified result ready to solve or practice.
Solve timed questions and test your accuracy.
Pick a difficulty or set your own polynomial and divisor $r$, then fill in the Ruffini table.
Correct verifications build your streak.
Bring down, multiply by $r$, add. Press Enter or Tab to move between cells.