SOLUTION: Use the formula to evaluate the series 2-10+50-250...-a6

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Question 856924: Use the formula to evaluate the series 2-10+50-250...-a6
Found 2 solutions by richwmiller, ewatrrr:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
Don't run things together. It is confusing.
Find the 6th term of the series 2-10+50-250,...
r= -5
Tn = t1 * r^(n - 1)
T6 = 2 * (-5)^(5)
T6=-6250

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

2-10+50-250...-a6

a%5Bn%5D+=+2%28-5%29%5E%28n-1%29

a%5B5%5D+=+2%28-5%29%5E%284%29+=+1250

a%5B6%5D+=+2%28-5%29%5E%285%29+=+-6250