Contour Integration — Examples
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✓ 12 results · all verified · 5 also independently AI-judged
Every result on this page is machine-checked by a proof checker and read in full and owner-audited; the judge is an additional, independent cross-model AI review of the proofs. The 7 not AI-judged were verified by owner audit (typically over a confirmed judge false positive), not failures.
1 · Prerequisites
Abstract Algebra
- Binary Operations, Monoids, Groups and Subgroups
- Cosets, Index and Lagrange's Theorem
- Divisibility, Euclidean Domains, Principal Ideal Domains and Unique Factorisation
- Ideals, Quotient Rings and the Isomorphism Theorems for Rings
- Normal Subgroups and Quotient Groups
- Polynomial Rings, the Division Algorithm and Roots
- Rings, Subrings, Integral Domains and Fields
- Simple Field Extensions and the Construction of the Complex Numbers
Complex Analysis
Linear Algebra
Real Analysis
- Absolute and Conditional Convergence; Rearrangement; Products
- Arc Length and Rectifiable Curves
- Bounded Variation and the Riemann–Stieltjes Integral
- Construction of the Real Numbers via Cauchy Sequences
- Construction of the Real Numbers via Dedekind Cuts
- Continuity, IVT, EVT, and Uniform Continuity
- Countability and Uncountability
- Foundations of the Real Numbers for Analysis
- Fundamental Trigonometric Identities
- Limits of Real Functions
- limsup, liminf, and Subsequential Limits
- Line Integrals and the Gradient Theorem
- Monotone Functions, Discontinuities, and Continuity Sets
- Monotone Sequences, Bolzano-Weierstrass, and Cauchy Completeness
- Power Series and Real-Analytic Functions
- Properties of the Integral and the Working FTC
- Rⁿ as a Normed Space; Vector-Valued Functions
- Roots, Rational Powers, and Classical Inequalities
- Sequences and Limits
- Sequences and Series of Functions; Uniform Convergence
- Series: Convergence and the Nonnegative Tests
- Sine, Cosine, and the Definition of Pi
- Suprema and Infima
- The Cantor Set, Baire Category, and Measure Zero in ℝ
- The Complex Exponential and Euler's Formula
- The Derivative and the Mean Value Theorems
- The Exponential Function
- The Fundamental Theorems of Calculus
- The Riemann Integral: Definition and Integrability
- The Total Derivative in ℝᵐ → ℝⁿ
- Topology of ℝ
Set Theory
2 · Logical flowchart
3 · Items
Example
An exponential contour integral approximated by Riemann sums and evaluated by parametrization and a primitive
Example
Integrating a complex polynomial along a segment and a parabola by a primitive and by parametrization
Example
The integral of complex conjugation from -1 to 1 differs along a semicircle and a polygonal path
Example
ML bounds for rational integrands on a semicircular arc and a line segment
Example
Direct computation of the integral of 1/(z-a) around a semicircle and a full circle centred at a
Example
The unit-circle integral of exp(z)/z is 2 pi i by uniform termwise integration
Example
Assembling a keyhole contour from two radial segments and two circular arcs
Example
The rectifiable Riemann–Stieltjes definition on an explicit polygonal contour with corners
Counterexample
Reversing orientation does not preserve a complex contour integral
False statement
FALSE: the modulus of a contour integral always equals the absolute line integral
False statement
FALSE: contour length depends only on the trace and ignores multiplicity
False statement
FALSE: parametrization independence makes orientation reversal leave every contour integral unchanged
Sources
- R. Howell and J. Mathews, Complex Analysis, §§6.1–6.2
- R. Howell and J. Mathews, Complex Analysis, §6.2
- A. Weber, Lecture Notes in Complex Analysis, Example 1.7.1
- L. Ahlfors, Complex Analysis, 3rd ed., Ch. 4, §1.3
- R. Howell and J. Mathews, Complex Analysis, Example 6.2.4
- Lars Ahlfors, Complex Analysis, third edition, Ch. 4 §1.2
- Russell Howell and John Mathews, Complex Analysis, §6.2