Proof for absolute convergence - sequences and series, Mathematics

Assignment Help:

Proof for Absolute Convergence

Very first notice that |an| is either an or it is - an depending upon its sign.  The meaning of this is that we can then say,

0 < an +| an| < 2 |an|

Now here, as we are assuming that ∑|an| is convergent then ∑ 2|an| is as well convergent since we can just factor the 2 out of the series and 2 times a finite value will still be finite.  Though this permits us to use the Comparison Test to say that ∑an + |an| is as well a convergent series.

 At last, we can write,

 ∑an = ∑ an + | an| - ∑ |an|                                                     

and thus ∑an is the difference of two convergent series and thus is also convergent.

Fact about Absolute Convergence

If ∑an is absolutely convergent then it is as well convergent.


Related Discussions:- Proof for absolute convergence - sequences and series

Mortgages, compute the monthly payment on a 30 year level payment mortagage...

compute the monthly payment on a 30 year level payment mortagagesasuming an annual mortgages principal of $400000

Draw the graph for finite state machine, Consider the finite state machine ...

Consider the finite state machine whose state transition table is : Draw the graph for it.  Ans: The graph for the automata according to the transition table is drawn b

What it means to count-learning to count, What do we understand by "being a...

What do we understand by "being able to count"? Think about the following situation before you answer. Example 1: Three year-old Mini could recite numbers from I to 20 in the co

Scatter graphs, Scatter Graphs - A scatter graph is a graph that compr...

Scatter Graphs - A scatter graph is a graph that comprises of points which have been plotted but are not joined through line segments - The pattern of the points will defin

Circles, examples of construction of excircles

examples of construction of excircles

NOWA method, solve the equation 540+115 using the NOWA method

solve the equation 540+115 using the NOWA method

Example of multiplying decimals, Example of Multiplying Decimals: Exa...

Example of Multiplying Decimals: Example:  0.45 x 10 = 4.5.  Same, while multiplying a decimal through 100, 1000, and 10,000, move the decimal point to the right the similar

Sequencing, jobs a b c d e f 1 15 8 6 14 6 26 ...

jobs a b c d e f 1 15 8 6 14 6 26 2 17 7 9 10 15 22 3 21 7 12 9 11 19 4 18 6 11 12 14 17

What is limit x tends to 0 log(1+x)/x to the base a?, Here we will use the...

Here we will use the expansion method Firstly lim x-0 log a (1+x)/x firstly using log property we get: lim x-0 log a (1+x)-logx then we change the base of log i.e lim x-0 {l

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd