Equation Solver
Solve polynomials up to cubic (with complex roots), 2×2/3×3 linear systems, and any f(x) = 0 numerically.
How it works
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Pick a mode: polynomial, linear system, or any equation f(x) = 0.
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Enter the coefficients — or type the full expression for the numeric mode.
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For f(x) = 0, set the search range; the solver scans it for sign changes.
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Read every root found — real and complex — rounded to 6 significant digits.
Frequently asked questions
Does it find complex roots?
Yes for polynomials: a quadratic or cubic with a negative discriminant reports its complex-conjugate roots in a + bi form. The numeric f(x) = 0 mode finds real roots only.
How does the numeric f(x) = 0 mode work?
It samples 200 intervals across your range, looks for sign changes, then refines each bracket with 50 bisection steps. Roots that merely touch zero (like x² at 0) are caught at sample points; very narrow spikes between samples can be missed, so tighten the range if you suspect one.
Why does my linear system say it has no unique solution?
Its coefficient matrix is singular (determinant 0) — the equations are dependent or contradictory, so there are either infinitely many solutions or none at all.
Is my equation uploaded to a server?
No — calculations run entirely in your browser — nothing is uploaded. You can solve as many equations as you like, free.
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