Calculus & Numerical Methods

Secant Method Root

Find a root using two initial guesses.

Formula

Formula
xn+1 = xn − fnxn−xn−1fn−fn−1

Variables

SymbolDefinitionType & rangeUnitsRole
f function expression / text x input
x₀, x₁ initial guesses computed result result

Try it yourself

Interactive calculator
math expression (e.g. x*x, sin(x))
Result

Worked examples

Example 1
Givenf(x) = x*x - 2, x₀ = 1, x₁ = 2
Result1.414213562
Example 2
Givenf(x) = exp(x) - 3, x₀ = 0, x₁ = 2
Result1.098612289