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Complex Analysis

An application of Cauchy's inequality

Let f be an entire function such that |f(z)|<=A|z|. Use Cauchy's inequality to show that f(z)=az for some complex constant a. See the attachment for a more complete description of the question and Cauchy's inequality.

Some simple applications of the Cauchy-Goursat theorem

Use the Cauchy theorem to show that the integral around the unit circle |z|=1, traversed in either direction, is zero for each of the following functions: 1) f(z)=z exp(-z) 2) f(z)=tan(z) 3) f(z)=Log(z+2) The attached file contains this question written more clearly with correct mathematical notation.

Green's Theorem: Contour Integrals

** Please see attached file for the complete problem description ** Complex Analysis Problem Problem. Show that if C is a positively oriented simple closed contour, then the area of the region enclosed by C can be written ..... Suggestion: You can use the form: R is a closed region for real valued functions. Does thi

Dividing by Zero and Imaginary Numbers

Mathematicians say that division by zero is forbidden. The expression 5/0, for example, is undefined. "Undefined" in this sense means "unable to be determined". Why is this? When we divide 5 by 5 (5/5) we get 1. Divide 5 by 2 we get 2.5. Each time we make the denominator smaller in the expression 5/x, the expression gets

Determine if the following equations are real or complex.

Determine if the following equations are real or complex; explain the answer in detail. Determine whether the following equations real or complex solutions; justify your answer. Note: It is not necessary to find the solutions; just determine if they are real or complex and explain why. a) 5x2 + 8x + 7 = 0 b) (7)1/2y2 - 6

Are the roots real, repeated real, or complex?

Determine if the following have a solution or not? justify answer. (apply the discriminant) are the roots real, repeated real, or complex? 1) 5x^2+8x+7=0 2) (7)^1/2y^2-6y-13(7)^1/2=0 3) 2x^2=x-1=0 4) 4/3x^2-2x+3/4=0 5) 2x^2+5x+5=0 6) p^2-4p+4=0 7) m^2=m+1=0 8) 3z^2+z-1=0

Solve the triangle and complex number

Please see attached file for full problem description. 1. B = 54 degrees, C = 112, and b = 18 2. Solve the equation on the interval [0, 2pi]: (cosx)^2 + 2 cos x + 1 = 0 3. Solve the triangle. Round lengths to the nearest tenth and angle measures to the nearest degree. C = 110°, a = 5, b = 11 4. Solve the triangle.

Evaluating complex numbers

Given the complex numbers z1 = 5 - j4 z2 = 4 + j z3 = -6 - j7 z4 = j2 Calculate, giving your answers in the form a + jb, the following:- (i) z4 - z1 + z2 (ii) 3z1 - 2z3 + z4 (iii) z1z2 (iv) z3/z2

Rearranging a Complex Expression

In the following equation, by equating real and imaginary parts, find expressions for R6 and L in terms of R1, R2, R3, R4, R5 and C, given that the frequency is one radian per second. R1 - j &#969;C = R2 + R3 R4 + R5 R6 + j &#969;L

Solve complex equation

In the following equation by equating real and imaginary parts, find expressions for R6 and L in terms of R1, R2, R3, R4, R5 and C, given that the frequency is one radian per second. See attached file for full problem description.

Quantitative Analysis - Waiting lines and queuing Theory models

I have some Quantitative Analysis questions I need help understanding. Waiting lines and queuing Theory models 1. The New Providence shopping mall is considering setting up an information desk manned by one employee. Because of the complex design of the mall, it is expected that people will arrive at the desk at about twi

Functions: Inverses and Composite Functions

The problems are all in multiple choice format so pick the most correct answer in each case and show your work. The degree three polynomial f(x) with real coefficients and leading coefficient 1, has -3 and + 4i among its roots. Express f(x) as a product of linear and quadratic polynomials with real coefficients. a. f(x) =

Complex Metric Spaces

Let (S,d) be a metric space and define the function u(x,y) = d(x,y)/(1+d(x,y)) for all x,y in S. (a) Prove that u is a metric on S with sup u(x,y) <= 1. (b) If S = C (complex) and d is the usual Euclidean metric d(z,w) = abs(z-w), then prove that sup u(z,w) = 1. (c) For 0 < r < 1, show that u(x,y) < r if and only

Complex Variables, Laurent Series and Uniform Convergence

(1) Let G = {z : 0 < abs(z) < R} for some R > 0 and let f be analytic on the punctured disk G with Laurent Series f(z) = sum a_n*z^n (from n = -oo to oo). (a) If f_n(z) = sum a_k*z^k (from k =-oo to n), then prove that f_n converges pointwise f in C(G,C) (all continuous functions from G to C (complex)); i.e., {f_n}

Derivation of Poisson Integral Formula for the Half-Plane

If is analytic in a domain containing the x-axis and the upper half-plane and in this domain, then the values of the harmonic function in the upper half-plane are given in terms of its values on the x-axis by (y>0). Below is an outline for the derivation, I just need to figure out how to justify the steps.

Complex Proof : Analytic Functions

Let f be an entire function such that |f(z)| &#8804; A|z| for all z in C for some fixed positive real number A. Use the attached theorem to show that f(z) = mz for some complex number m.

Quantitative Analysis in Business Decisions

Mr. Davison has been operating a small bicycle shop at the same location near Aspen, Colorado for 50 years. What type of decisions must he make in operating his business? On what basis would he likely be making these decisions? How do you think Mr. Davison would respond to a suggestion that he hire a quantitative analyst to assi

Systems of Complex Equations

x ------------------ = 0.007 754 1 + i --------- y 42425 x -------------------------------------- = 1 754 (1+ i -------) *500* (1 + i 41.47) y USING THESE TWO EQUATIONS SOLVE FOR X=? AND Y=?

Sample Mobius Transformations

Prove that if T is a Mobius transformation such that T(0) = 0, then T may be written as T(z) = z/(cz+d) for some choices of c and d.

Complex Number Form : a+bi

Write each expression in the form of a+bi, where a and b are are real numbers 1. -3i/3-6i 2. -2-sqrt-27/-6

Complex Numbers and the Roots of an Equation

If the solution to an equation is imaginary or irrational, it takes a bit more effort to check. Replace x by each given number to verify the following statement. Both 2+3i and 2-3i satisfy x^2 -4x+13=0

Write a cis expression in standard complex form (a+bi)

Use Demoivre's theorem to write [3 cis(pi/2)]squared in the form a+bi without trigonometric functions. Find the real and complex solution of the equation Xsquared - 8 = 0 Find the angle between the two vectors (5,2) and (-2,5)