Thread: Writing the Sum Using Sigma Notation

Alright, it goes hand-in-hand with a previous topic titled "Summation Formulas" but yet...it's different at the same time.

This time they give me two series:


1.

2.


My first reaction was that I would have to find the formula myself, where it starts, and where it ends. Simple...except not so much.

The second one is possibly .

Although that would be way to simple, hehe.
The first one though, I can't seem to find a proper equation that fits the numbers given.

The answer to the second one is correct.

You could even say

Can't see a pattern in the first one yet.

Yeah, I dunno what's going on with the first one. I spent at least an hour or two going over it but it's harder then it looks...and it looked pretty hard to start with.

Oh, I also made a mistake on number one, accidently left out a number. Fixed it.

Should be:

Originally Posted by UnstoppableBeast

Alright, it goes hand-in-hand with a previous topic titled "Summation Formulas" but yet...it's different at the same time.

1.

I think it ought to be .

In which case it would be

Is it possible the second term has to be in stead of ?

Sadly no. It would've been easier that way but I'm sure of what the question is asking, I have the paper right in front of me.

Maybe the person who made the packet made a mistake, seems as likely as anything.