would you mind explaining that again. I dont get how you get that?

Thanks

Printable View

- May 21st 2008, 11:10 AMtaurus
- May 21st 2008, 11:15 AMKrizalid
Following up on TheEmptySet's post.

We have

Since

back substitute and

This result is called as "telescoping sum." - May 21st 2008, 11:19 AMMoo
- May 21st 2008, 11:22 AMtaurus
last question

Moo

on that new way you showed me how would i get the sum?

i stick values for n of 0, 1, 2, 3... and see if there is number not reapeating? - May 21st 2008, 11:23 AMMoo
- May 21st 2008, 11:27 AMtaurus
but for the new method seems more understandable

i put n = 1 and got -1/30 which aint the sum:? - May 21st 2008, 11:32 AMMoo
It's n=1 in :)

- May 21st 2008, 11:41 AMtaurus
but you said

(-1/n+4) + (1/n+5)

why dont you add? - May 21st 2008, 11:42 AMMoo
Because 1/(n+5) annulates with the following term, and so on...

Just write the few first terms of the series on a paper, and you will see that..