Please read each line carefully---
PROVE OR DISPROVE 1. If {an} is a non-increasing sequence of positive real numbers such that...
3) Let (an)2- be a sequence of real numbers such that lim inf lanl 0. Prove that there exists a subsequence (mi)2-1 such that Σ . an, converges に1
1. Let {n} be a sequence of non negative real numbers, and suppose that limnan = 0 and 11 + x2 + ... + In <oo. lim sup - n-00 Prove that the sequence x + x + ... + converges and determine its limit. Hint: Start by trying to determine lim supno Yn. What can you say about lim infn- Yn? 3 ) for all n Expanded Hint: First, show that given any e > 0 we have (...
an+1 for all values of n. What 1. Let {an} be a sequence of positive, real numbers such that is lim an? Explain how you got your answer. an 3n + 1 n-> 2. Let {an} and {bn} each be a sequence of positive real numbers. You know that ) bn converges and k=1 21. Your buddy Ron concludes that the series converges also. Select an item below and n70 bm 10. explain. lim An _ 1001
The work provided for part (b) was not correct. (a) Suppose lim(Fm) = 1. Prove or disprove: There exists no E N such that IFml > 0.99 for all o (b) Prove or disprove:If (an) converges to a non-zero real number and (anbn) is convergent, then (bn) is convergent. RUP ) Let an→ L,CO) and an bn→12 n claim br) comvetgon Algebra of sesuenes an (a) Suppose lim(Fm) = 1. Prove or disprove: There exists no E N such that...
5. Let {xn} and {yn} be sequences of real numbers such that x1 = 2 and y1 = 8 and for n = 1,2,3,··· x2nyn + xnyn2 x2n + yn2 xn+1 = x2 + y2 and yn+1 = x + y . nn nn (a) Prove that xn+1 − yn+1 = −(x3n − yn3 )(xn − yn) for all positive integers n. (xn +yn)(x2n +yn2) (b) Show that 0 < xn ≤ yn for all positive integers n. Hence, prove...
Exercise 15: Let (cn) be a sequence of positive numbers. Prove: lim infºn+1 < lim infch/n. n700 Cnn +00 What is the corresponding inequality for the lim sup?
18. If ai, az, as,... is a bounded sequence of real numbers, define lim sup an (also denoted lim an) to be --+ n+ l.u.b. {z ER: an > & for an infinite number of integers n} and define lim inf an (also denoted lim an) to be g.l.b. {ER: An <for an infinite number of integers n}. Prove that lim inf an Slim sup an, with the equality holding if and only if the sequence converges. 19. Let ai,...
Problem 1 Let {ak} and {bk} be sequences of positive real numbers. Assume that lim “k = 0. k+oo bk 1. Prove that if ) bk converges, so does 'ak k=1 k=1 2. If ) bk diverges, is it necessary that ) ak diverges? k=1 k=1
Suppose an- is a decreasing sequence of non-negative numbers (that is, 0 S an+1 S an for all n) a) Show that 2K a1 + - n-1 b) Suppose Σ-1 an is a convergent series. Use part a to show that Σ-1 2na2n converges. HINT: recall the monotonic sequence theorem c) Show that n-1 d) Suppose that Ση_1 2na2n is a convergent series. Use part c to show that Ση-1 an e shown that Ση.1 an conv Σ-1 2na2n converges....
1. Let Xn ER be a sequence of real numbers. (a) Prove that if Xn is an increasing sequence bounded above, that is, if for all n, xn < Xn+1 and there exists M E R such that for all n E N, Xn < M, then limny Xn = sup{Xnin EN}. (b) Prove that if Xn is a decreasing sequence bounded below, that is, if for all n, Xn+1 < xn and there exists M ER such that for...