SOLUTION: Hey! I'm trying to figure out what the general formula is based on the following sequence: {2/3, -3/5, 4/7, -5/9} So I believe that the numerator is something like (n+1) but

Algebra ->  Sequences-and-series -> SOLUTION: Hey! I'm trying to figure out what the general formula is based on the following sequence: {2/3, -3/5, 4/7, -5/9} So I believe that the numerator is something like (n+1) but      Log On


   

Question 1081833: Hey!
I'm trying to figure out what the general formula is based on the following sequence: {2/3, -3/5, 4/7, -5/9}
So I believe that the numerator is something like (n+1) but I can't for the life of me figure out the bottom or the negatives..
Thanks!
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Sign alternates with successive terms.
Numerator increases by 1 each term, and denominator increases by 2 for each successive term.

%28-1%29%5E%28n%2B1%29 necessary factor for each n term.

%282%2B%28n-1%29%29%2F%283%2B2%28n-1%29%29

Put those together:
%28%28-1%29%5E%28n%2B1%29%29%28%282%2B%28n-1%29%29%2F%283%2B2%28n-1%29%29%29

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Hey!
I'm trying to figure out what the general formula is based on the following sequence: {2/3, -3/5, 4/7, -5/9}
So I believe that the numerator is something like (n+1) but I can't for the life of me figure out the bottom or the negatives..
Thanks!
The correct rule is: highlight_green%28%28%28n+%2B+1%29%2F%282n+%2B+1%29%29+%2A+-+1%5E%28n+%2B+1%29%29%29