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Complex Analysis

Radius of Convergence and Abel's Theorem in Complex Analysis

A) I want to prove that if sum of a_n(z-a)^n have radius of convergence 1 and if the sum a_n converges to A then lim (r -> 1- ) of the sum (a_n r^n) = A. ( I believe z here is a complex number). B) Using Abel's theorem, prove that log2 = 1 - 1/2 + 1/3 - ...

I need help with these five algebra problems.

BACKGROUND INFORMATION: A simple pendulum, such as a rock hanging from a piece of string or the inside of a grandfather clock, consists of a mass (the rock) and a support (the piece of string). When the mass is moved a small distance away from its equilibrium point (the bottom of the arc), the mass will swing back and fort

Complex Analysis : Analytic Functions as Mappings

1). Let G be a region and suppose that f : G -> C ( C is complex plane) is analytic such that f(G) is a subset of a circle. Show that f is constant. 2). If Tz = (az + b)/(cz + d), find necessary and sufficient conditions that T(t) = t where t is the unit circle { z: |z| = 1}. My solution for number 2 is : T(t) = t , which

Complex Analysis : Mobius Transformation

1). Let D = {z: |z| < 1 } and find all Mobius transformations T such that T(D) = D. 2). Show that a Mobius transformation T satisfies T(0) = infinity and T ( infinity) = 0 if and only if Tz = az^-1 for some a in C ( C is complex plane).

Complex Numbers : RSA Cipher and Summation

A=1,B=2,C=3,D=4,E=5,........X=24,Y=25,Z=26 It is enciphered using the rule 35 R (m)=m (mod 91) 35 The resulting ciphertext is ( 73,14,23,73,23) Verify the rule given satisfy the condition for an RSA cipher. Using the repeated squaring technique decipher the ciphertext and find the message

Polynomial Equations : Complex Solutions, Conjugates and Shift Operator

Prove that if p is a polynomial with real coefficients, and if is a (complex) solution of P(E)z = 0, then the conjugate of z, the real part of z, and the imaginary part of z are also solutions. Note: This is from a numerical analysis course, and here P(E) refers to a polynomial in E, the "shift operator" for a sequence.

Analytic functions in complex plane

1). Determine the set A such that For r > 0 let A ={w, w = exp (1/z) where 0<|z|<r}. 2).Prove that there is no branch of the logarithm defined on G= C-{0}. ( C here is the complex plane). ( Hint: suppose such a branch exists and compare this with the principal branch). I want detailed proofs and please prove ever

Analytic Function Proofs and Real Functions

1) Show that the real part of the function z^(1/2) is always positive. 2) Suppose f: G --> C ( C complex plane) is analytic and that G is connected. Show that if f(z) is real for all z in G, then f is a constant.

Complex Eigenvalues Investigated

Find the solution to the given system for the given initial condition x'(t)= [1,0,-1;0,2,0;1,0,1]x(t) for a.) x(0)= [-2;2;-1] b.) x(-pi)=[0;1;1]

Continuity complex plane

Let G be an open subset of C ( complex plane) and let P be a polygon in G from a to b. Use the following 2 theorems to show that there is a polygon Q in G from a to b which is composed of line segments which are parallel to either the real or imaginary axes. The 2 theorems are: 1). Theorem: Suppose f: X --> omega is continuou

Metric spaces and the topology of complex plane

Show that { cis k : k is a non-negative ineger} is dense in T = { z in C ( C here is complex plane) : |z| = 1 }. For which values of theta is { cis ( k*theta) : K is a non-negative integer} dense in T ? P. S. cis k = cos k + i sin k, i here is square root of -1. I want a full justification for each step or claim.

Stereographic projection on complex plane

Let V be a circle lying in S. Then there is a unique plane P in R^3 such that p / S = V ( / = intersection). Recall from analytuc geomerty that P = { (x_1,x_2,x_3) : x_1 b_1 + x_2 b_2 + x_3 b_3 = L, where L is a real number}. Where ( b_1,b_2,b_3) is a vector orthogonal to P . It can be assumed that (b_1)^2 + (b_2)^2 + (b_3)

DeMoivre's Theorem and Power of Complex Numbers

See the attached file for complete equations --- Use DeMoivre's Theorem to find the indicated power of the following complex numbers: 1. Find the fourth roots of 256(1+&#61654;3i ) 2. Find all solutions of the equation x3 &#61485; 27i = 0 [please show all the steps, including the algebraic ones] ---

Harmonic Functions and Cauchy-Riemann Equations

15. Determine whether or not the given function u is harmonic and, if So, in what region. If it is, find the most general conjugate function v and corresponding analytic function f (z). Express f in terms of z. Please see the attached file for the fully formatted problems.

Complex Variables : Region of Flow, Fluid Presure and Speed of Fluids

4. Show that the speed of the fluid at points on the cylindrical surface in Example 2, Sec. 108. (below) is 2A| sin &#952;| and also that the fluid pressure on the cylinder is greatest at the points z = ±1 and least at the points z = ± i --- - Show the speed of the fluids... - At an interior point of a region of flow...

Two Complex Variable Problems

See the attachment for the problems. --- - the image of the closed rectangular region... - principal branch of the square root... --- (See attached file for full problem description).

Four complex variable problems (87-4,5,6,10)

See the attachment for the problems --- - Find the bilinear transformation that maps... - Show the disposition of two linear fractional transformations... - A fixed point of transformation w = f(z)... - Show that there is only linear fractional transformation that maps... --- (See attached file for full problem descri

Four complex variable questions (83-5, 85-5, 7, 13)

See the attachment for the problems. --- - Find the region onto which the half plane y>0... - Find the image of the quantrant x>1, y>0... - Describe geometrically the transformation w=1/(z-1). - Using the exponential formz = re^(i x theta) of z... ---- (See attached file for full problem description)