SOLUTION: Find the sum of the first twenty terms of the sequence 1/2,1/4,0,... -17/4 where -17/4 is the 20th term.

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Question 839000: Find the sum of the first twenty terms of the sequence 1/2,1/4,0,... -17/4 where -17/4 is the 20th term.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

 sequence 1/2,1/4,0,... -17/4 where -17/4 is the 20th term

(Arithmetic Sequence d = -1/4)

S%5Bn%5D=%28n%2F2%29%282%2Aa%5B1%5D%2B+%28n-1%29d%29

0r  S%5Bn%5D=%28n%28a%5B1%5D%2Ba%5Bn%5D%29%29%2F2

S%5B20%5D=%2820%281%2F2+%2B+-17%2F4%29%29%2F2+=+highlight%28-37.5%29++

Wish You the Best in your Studies.