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Real Analysis

Limit Proofs

Prove the following a) If lim n-->infinity (a_n*b_n) exists and lim n--> infinity (a_n) exists, then lim n -->infinity (b_n) exists. b) If lim n--> infinity (a_n) = 0 and {b_n} is bounded, then lim n-->infinity (a_n*b_n) exists and equals 0. c) If lim superior (a_n) exists, then {a_n}_n is bounded above.

Limit Inferior

Suppose a_n >0 for each n in N and lim inf (a_n) > 0. Prove there is a number a>0 st a_n >/= a for all n in N. (limit n--> infinity)

Series : Domain of Convergence

Find the domain of convergence of each of the following: a) Summation from n = 1 to infinity of [(z-1)^2n]/((2n)!) b) Summation from n = 1 to infinity of [(n^2 + 1)/(2n + 1)]z^n c) Summation from n = 1 to infinity of [(z + 1)^n]/n d) Summation from n = 0 to infinity of [(z - 1)/(z + 1)]^n

Series Convergence

Determine if the following series converges absolutely, conditionally, or not at all. Summation from n=1 to infinity (-1)^n (n+1)/n^2

Methods of Real Analysis by Richard Goldberg

(See attached file for full problem description with equations) --- 9.3-5 Let {f_n} (from n - 1 to infinity) be a sequence of functions on [a,b] such that (f_n)'(x) exists for every x is an element of {a,b](n is an element of I) and (1) {(f_n)(x_0)} (from n=1 to infinity) converges for some x_0 is an element of [a,b]. (2

95.3

(See attached file for full problem description with equations) --- 9.5-3 Without finding the sum of the series Show that --- We use the book Methods of Real Analysis by Richard Goldberg.

95.1

(See attached file for full problem description) We use the book Methods of Real Analysis by Richard Goldberg.

94.8

(See attached file for full problem description with equations) --- 94.8 Let be a sequence of functions on E such that where . Let be a nonincreasing sequence of nonnegative numbers that converges to 0. Prove that converges uniformly on E (Hint: See 3.8C) Theorem 3,8C Let be a sequence of real numbers whos

94.5

(See attached file for full problem description with equations) --- 9.4-5 Show that the series is uniformly convergent on [0,A] for any A>0. Prove that --- We are using the book of Methods of Real Analysis by Richard Goldberg.

94.2

(See attached file for full problem description with equations) --- 9.4-2 Does the series converge uniformly on (Hint: Find the sum of the series for all x) --- We are using the book of Methods of Real Analysis by Richard Goldberg.

Limit

(See attached file for full problem description with equation and proper symbols) --- 9.2-10 If be a sequence of functions that converges uniformly to the continuous function , prove that ---

Mapping, Contraction and Fixed-Point Theorem

(See attached file for full problem description with proper equations) --- 3. Let T(x) = x^2 Show that T is a contraction on (0, 1/3] , but that T has no fixed point on this interval. Does this conflict Theorem 6.4? Explain. Note: We are using the book Methods of Real Analysis by Richard R. Goldberg. This

Convergence of series (complex)

Find the radius of convergence of the series sum from n = 1 to infinity of n^3(z/3)^n. Does this series converge at any point on the boundary of the disk of convergence?

Limits

As x approaches -2 from the left, what is the limit of (square root of x^2 +5) / (x+2) Please show work if you can. Choices are A. 3/2, B. 0, C. -infinity D. -1, E. + infinity

Trigonometric Limits

lim [(cos x-1)x]/sin x x->0 Please see the attached file for the fully formatted problems.

Fibonacci Sequences, Convergence and Limits

(a) find the first 12 terms of the Fibonacci sequence Fn defined by the Fibonacci relationship Fn=Fn-1+Fn-2 where F1=1, F2=1. (b) Show that the ratio of successive F's appears to converge to a number satisfying r2=r+1. (c) Let r satisfy r2=r+1. Show that the sequence sn=Arn, where A is any constant, satisfies the Fi

Increasing, Bounded, Sequences and Series, Limits and Convergence

The sequence Sn = ((1+ (1/n))^n converges, and its limit can be used to define e. a) For a fixed integer n>0, let f(x) = (n+1)xn - nxn+1 . For x >1, show f is decreasing and that f(x) . Hence, for x >1; Xn(n+1-nx) < 1 b) Substitute the following x-value into the inequality from part (a)

Real Analysis - Limits of Sequences

Suppose that {an} and {bn} are sequences of positive terms, and that the limit as n goes to infinity of (an/bn) = L > 0. Prove that limit as n goes to infinity of an is positive infinity if and only if the limit as n goes to infinitiy of bn is positive infinity. Here is what I have for proving the first way: Suppose that

Uniform Convergence of Series

If |fn(x)| < gn(x) for all nE R and every x E[a,b] , and the series... converges uniformly in [a,b], then ... converges uniformly in [a,b]. Please see the attached file for the fully formatted problems.