# Homework Help: Bounded sequence converges.

1. Nov 9, 2011

### kmikias

1. The problem statement, all variables and given/known data
A bounded monotone sequence converges.
Proof
for bounded monotone increasing sequence and decreasing sequence.
Does both them converges?

2. Relevant equations
So, I used the least upper bound and great lower bound to prove increasing sequence and decreasing sequence.

Property of LUB and GREAT LOWER BOUND.

3. The attempt at a solution

a bounded monotone increasing sequence to converge....
Proof.
a_{n} is monotone increaing if n > N(ε), then a_{n}≥ a_{N(ε)} > L -ε. But a_{n) ≤ L.
thus L - ε < a_{n} ≤ L for n > N(ε); that is | a_{n} - L | < ε for n>N(ε). Δ

Proof for a bounded monotone decreasing sequence to converge..
this is where i got lost.

so i used great lower bound to do the proof.
we know G.L.B has this two property
1. a_{n} ≥ L for every n
2. for ε > 0, there exist a positive number N(ε) SUCH THAT a_{N(ε)} < L-ε

so
a_{n} is monotone decresing if n > N(ε), then L ≤ a_{n} ≤ L +ε. am kind of lost here.

Last edited: Nov 9, 2011
2. Nov 9, 2011