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Determine the following sum,,

  • Thread starter Lord Dark
  • Start date
  • #1
121
0

Homework Statement


hi guys ,, i hope you all are fine ,,
i have a problem with this question :
Determine the following sum:
1-4+9-16+25-...-10000+10201

Homework Equations





The Attempt at a Solution


i don't know where even to start ,, can anyone give me an idea how to solve problems like these ??
 

Answers and Replies

  • #2
238
0
Do you see a pattern between the numbers? Try to write it in summation form i.e. [tex] \sum_{i=1}^n \left\{... \right\}[/tex]; after you see the pattern, you should know what n is. Then you can find the sum.
 
  • #3
121
0
i got an idea that Sum (1,51) (2x-1)^2-(2x-2)^2 = 5151
is it right ??
 
  • #4
Dick
Science Advisor
Homework Helper
26,258
618
The number is right. If you are clear how to get it from your expression, you should be ok.
 
  • #5
121
0
thanks very much :D , i just needed to be sure of my way
 
  • #6
7
0
You're wasting your time: That series does not and cannot converge. How could it? The terms get bigger and bigger.

Read up on what it means for an infinite series to converge.
 
  • #7
761
13
You're wasting your time: That series does not and cannot converge. How could it? The terms get bigger and bigger.
No, you're wrong there's no infinite series.

Read up on what it means for an infinite series to converge.
Maybe YOU should read better.
 
  • #8
33,173
4,858
You're wasting your time: That series does not and cannot converge. How could it? The terms get bigger and bigger.

Read up on what it means for an infinite series to converge.
As Dirk pointed out, and as you can see in the OP, this is a finite sum.
 

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