Root finding#

The Babylonian square-root rule and bisection, Newton-Raphson’s tangent iteration, Halley’s cubically convergent method, and Aitken/Steffensen acceleration, each with its empirical convergence order measured; then Newton’s method for systems of equations and Broyden’s quasi-Newton method, which saves the Jacobian evaluations.

An animation runs Newton against bisection on the graph of \(f\).

The Babylonian square root and bisection

The Babylonian square root and bisection

Newton-Raphson’s method: tangent lines and quadratic convergence

Newton-Raphson's method: tangent lines and quadratic convergence

Halley’s method: cubic convergence

Halley's method: cubic convergence

Aitken’s delta-squared process and Steffensen’s method

Aitken's delta-squared process and Steffensen's method

Simpson’s Newton method for systems of equations

Simpson's Newton method for systems of equations

Broyden’s quasi-Newton method

Broyden's quasi-Newton method

Animated: Newton’s tangents against bisection’s halving

Animated: Newton's tangents against bisection's halving