2.1/
Bisection Technique
- What?
- Why?
- Method:
- Algorithm:
- Drawbacks:
- Stopping Criterions:
The best criterion is:
- Convergence:
It:
- Rate of Convergence \ Error Bound:
- The problem of Percision:
We use,
- The Signum Function:
We use,
2.2/
Fixed-Point Problems
- Fixed Point:
- Root-finding problems and Fixed-point problems:
Root Finding and Fixed-point problems are
- Why?:
- Existence and Uniqueness of a Fixed Point.:
Fixed-Point Iteration
- Approximating Fixed-Points:
- Algorithm:
- Convergence:
- Fixed-Point Theorem:
- Error bound in using \(p_n\) for \(p\):
Notice:
- Fixed-Point Theorem:
- Using Fixed-Points:
Question: \(\ \ \ \ \\)
Answer:
- Newton’s Method as a Fixed-Point Problem:
2.3/
Newton’s Method
- What?:
- Newton’s (or the Newton-Raphson) method is:
- Newton’s (or the Newton-Raphson) method is:
- Derivation:
- Algorithm:
- Stopping Criterions:
Convergence using Newton’s Method
- Convergence Theorem:
Theorem:
The crucial assumption is
Theorem 2.6 states that,
(1)
(2)
The Secant Method
-
What?
In Newton’s Method
We approximate \(f'( p_n−1)\) as:
To produce:
- Why?
\(\ \ \ \ \ \ \ \ \\):
Frequently,
Note:
- Algorithm:
- Convergence Speed:
The Method of False Position
- What?
- Why?
- Method:
- Algorithm:
2.4/
Order of Convergence
- Order of Convergence:
- Important, Two cases of order:
- An arbitrary technique that generates a convergent sequences does so only linearly:
Theorem 2.8 implies
- Conditions to ensure Quadratic Convergence:
-
Theorems 2.8 and 2.9 imply:
(i)
(ii)
- Newtons’ Method Convergence Rate:
Multiple Roots
- Problem:
- Zeros and their Multiplicity:
- Identifying Simple Zeros:
- Theorem:
- Generalization of Theorem 2.11:
The result in Theorem 2.12 implies
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- Why Simple Zeros:
Example:
- Handling the problem of multiple roots:
- We \(\ \ \ \ \ \ \ \ \ \ \ \ \ \ \\)
- We define \(\ \ \ \ \ \ \ \ \ \\) as:
- Derivation:
- Properties:
-
2.5/
Aitken’s \(\Delta^2\) Method
- What?
- Why?
- Derivation:
- Del [Forward Difference]:
- \(\hat{p}_n\) [Formula]:
- Generating the Sequence [Formula]:
Steffensen’s Method
- What?:
- Zeros and their Multiplicity:
- Difference from Aitken’s method:
- Aitken’s method:
- Steffensen’s method:
Notice
- Aitken’s method:
- Algorithm:
- Convergance of Steffensen’s Method:
2.6/
Algebraic Polynomials
- Fundamental Theorem of Algebra:
- Existance of Roots:
- Polynomial Equivalence:
This result implies
Horner’s Method
- What?
- Why?
- Horner’s Method:
- Algorithm:
- Horner’s Derivatives:
- Deflation:
- MatLab Implementation:
Complex Zeros: Müller’s Method
- What?
- It is a:
- Müller’s method uses
- It is a:
- Why?
- First:
- Second:
If the initial approximation is a real number,
- First:
- Complex Roots:
- Algorithm:
- Calculations and Evaluations:
Müller’s method can: