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Introduction to Numerical Analysis I. Root Finding without Derivatives . MATH/CMPSC 455. Newton’s Method. Give . No. Converge?. Yes. Out put . Quadratic convergence of Newton’s method. Definition: The iteration is quadratically convergent if .
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Introduction to Numerical Analysis I Root Finding without Derivatives MATH/CMPSC 455
Give No Converge? Yes Out put
Quadratic convergence of Newton’s method Definition: The iteration is quadratically convergent if Theorem: Let be twice continuously differentiable. If , then Newton’s method is locally and quadratically convergent to the root.
Example: Use Newton’s method to find root of Theorem: Assume that the (m+1)-times continuously differentiable function has a multiplicity m root. Then Newton’s method is locally and linearlyconvergent to the root. Modified Newton’s Method:
Example: Apply Newton’s Method to the following function with starting guess 1 -1
Give No Converge? Yes Out put
Other Methods without Derivatives • Method of False Position: • Similar to Bisection method, but where the midpoint is replaced by a Secant Method-like approximation. • Muller’s Method: • Muller’s Method uses three previous points to draw a parabola through them, and intersect the parabola with the x-axis. • Inverse Quadratic Interpolation: • IQI is similar with Muller’s Method. However, the parabola is of the form • Hybrid Method