# Thread: two sequence and series problems

1. ## two sequence and series problems

I need to calculate the first 10 N's series, in convergant series. If a3=(-1)/24 and a6=1/3

And another one

Check where the limit if heading to

lim (1+0,5+0,25+0,0625+....+0,5^n)
n-infinity

I need to return this tomorrow, so i am really desperad seeking help here
Those are the only ones I can't handle. Plese help me if you can solve this !

2. Originally Posted by hlolli
And another one

Check where the limit if heading to

lim (1+0,5+0,25+0,0625+....+0,5^n)
n-infinity

I need to return this tomorrow, so i am really desperad seeking help here
Those are the only ones I can't handle. Plese help me if you can solve this !
This is a geometric series, and you should know that:

$\displaystyle \frac{1}{1-r}=1+r+r^2+... \ \ \forall r \in [0,1)$

(your first question is incomprehensible)

CB

3. Thank you, I'm trying best I can to translate to english. Math words in Icelandic are so surreal. But I think I got all problems right now.