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## #1 Re: Help Me ! » Calculation with a given accuracy » 2013-02-12 03:26:38

I  do not really know, I guess I'll leave it as it is. Too much time has been spent on it. There are other problems to solve. Thank you for support, bobbym!

## #2 Re: Help Me ! » Calculation with a given accuracy » 2013-02-12 03:08:45

Epsilon is given:
10^-3
10^-4
10^-5
10^-6
So there is nothing to choose from, it's already known. As I said before the script already does more calculations than needed. What I am wondering about now is why there are only 4 "epsilons", although it is said that I should run the summation for the first 10 terms (what I can't technically do though :-) ).

## #3 Re: Help Me ! » Calculation with a given accuracy » 2013-02-12 02:50:46

The table should be like this:

Accuracy (they call it epsilon) | Sum | Term (K)

## #4 Re: Help Me ! » Calculation with a given accuracy » 2013-02-12 02:46:24

sorry for an ambiguous post, you did not understand me right, in the previous post by "the actual error" I meant they do not want any error, they just require to specify accuracy (10^-3, 10^-4, 10^-5, 10^-6).

## #5 Re: Help Me ! » Calculation with a given accuracy » 2013-02-12 01:15:06

We can improve that easily. Are they still forcing people to use that language?

yep, they are. ((

Why did I pick x = 1?

No idea. Maybe because it is short and simple!?))

Also, one more thing turned out to be wrong, I already edited my code so it returns K, sum and Error, but have just noticed that they do not want the actual error to be on the list, they want me to calculate sums with given accuracy (10^-3, 10^-4, 10^-5, 10^-6) and specify this accuracy in the error column. I guess I'm just gonna leave it as it is. I think the script currently does even more calculations than required.

## #6 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 22:23:48

thank you, bobbym, it is quite clear now!

## #7 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 22:04:35

Yeah, seems to be clear so far. And what i see is that the first term = sum #1, and the following terms correspond to alternating errors from the table kindly provided by you.

## #8 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 21:34:09

how come it can be easier than subtracting two numbers?))

## #9 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 21:17:16

LOL!)) I am back!!

It seems that to calculate the alternating error you go down the list and subtract the smaller number from the larger one.

Isn't this correct?

## #10 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 04:55:53

Nice! I got it! Thank you for making it challenging!))

Since I cannot determine the number which this series converges to (I can run my summation script for only 9 terms), I'll modify my code to return only alternating errors.

I hope I won't run into any more difficulties with this problem. Thanks!!)

## #11 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 04:40:56

the actual error I guess supposed to be the difference between the number which the series converges to and the current sum.

## #12 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 04:38:06

It seems that to calculate the alternating error you go down the list and subtract the smaller number from the larger one. And as for the actual error - no idea. They seem to look just slightly different from alternating errors.

## #13 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 01:59:13

bobbym,

thank you for the table. But what I need is the formula that will allow me to calculate those errors. I have figured out how to calculate sums, but do not now how I can get the error for each sum.

## #14 Re: Help Me ! » Calculation with a given accuracy » 2013-02-11 00:03:09

I would like to. Sorry, I really do not understand this.

## #15 Re: Help Me ! » Calculation with a given accuracy » 2013-02-10 23:35:27

bobbym,

I mean the column "epsilon" . I believe that sum of the series is the "sum" column, isn't it?
What I mean is that I don't know what to put into the epsilon column.

## #16 Re: Help Me ! » Calculation with a given accuracy » 2013-02-10 20:57:39

pls. don't judge me harshly, but the problem has not been completely solved yet (but the deadline is coming... uggg)

You can see what I got so far in the attached picture.

I am able to run summation only for its first 9 terms. Then the denominator apparently gets to large for Turbo Pascal and it returns me an error.

What I cannot understand is the epsilon column. bobbym, can u pls. tell me what was the algorithm to find those errors in the table you posted. Shall I now, having my table, somehow derive them from the sums that I got? Thanks!

PS
I cannot upload the image, so it can be found here - master-chinese.ru/screen_shot.jpg

## #17 Re: Help Me ! » Calculation with a given accuracy » 2012-12-25 03:40:03

Appreciate your help, bobbym! Thanks! Reading about Bessel function right now. darn, it is not fun at all)) Or may be I just need some sleep...

## #18 Re: Help Me ! » Calculation with a given accuracy » 2012-12-25 03:30:11

Yeah, they apparently forgot to include this into my problem. Sorry.

## #19 Re: Help Me ! » Calculation with a given accuracy » 2012-12-25 03:18:46

The other variant states that absolute x is < 1. But on my variant there is no such a condition. They only require x not to be equal to zero. No other restrictions specified.

## #20 Re: Help Me ! » Calculation with a given accuracy » 2012-12-25 02:49:43

OK. thanks! I'll be around.))

## #21 Re: Help Me ! » Calculation with a given accuracy » 2012-12-25 02:38:38

bobbym,

Thank you for your help! I will read up on that. Too hard to get it right away. I've been trying to understand this problem for a couple of days already. (( Your help is highly appreciated!!

## #22 Re: Help Me ! » Calculation with a given accuracy » 2012-12-25 02:16:49

Unfortunately I do not know what X is and this makes  it more confusing. Two things I am currently confused about are what I should do with X here and how to determine the level of accuracy. Can you pls. formulate what I should search for to find some information on solving for this kind of problems. Thanks!

## #23 Help Me ! » Calculation with a given accuracy » 2012-12-25 01:42:08

Serj
Replies: 43

Hello, guys! Plzz help me out here..

The proplem:

Real numbers X, ε given (X not equal to 0, ε > 0). Calculate the sum of the series  with the accuracy ε (ε = 10^-3, 10^-4, 10^-5, 10^-6) and specify the number of summands. Put results into columns ε, sum, N. Run the calculation only for the first 10 terms. Numerical part of the problem is attached.

This actually is a problem for my programming class, but I can't understand math behind the problem. What is X here? How can I perform these calculations with the given accuracy. Pls. advice if possible. Thanks!!