Equation Root Finder

Equation Root Finder

Bisection approximates one real root, not every solution. Both endpoints must be finite and the left must be smaller. A zero function value at an endpoint returns that endpoint; otherwise the endpoint function values must have opposite signs. Continuity throughout the interval is essential. A sign change across an asymptote does not establish a root, and no sign change does not prove that no root exists.

The calculation performs at most 100 iterations and may stop earlier when a sampled function value is exactly zero. Displayed digits are rounded, not a guaranteed error bound. Small nonzero values below 1e-9 and values of magnitude at least 1e15 use scientific notation with up to 13 significant digits; other values use up to 12 decimal places. A small residual f(x) alone does not prove the root is accurate.

Use explicit multiplication (2*x), ^ for powers, a dot for decimal literals, and parentheses. x**2 and 2x are unsupported. log and ln mean the natural logarithm; sin, cos and tan take radians. Whitespace is ignored; the remaining expression must not exceed 240 characters. Processing stays in the browser.