SOLUTION: What is the sum of the infinite geometric series?
(-15)+ 0+ 15 +30+.....+195
Please show me step by step, thank you in advance!
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-> SOLUTION: What is the sum of the infinite geometric series?
(-15)+ 0+ 15 +30+.....+195
Please show me step by step, thank you in advance!
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Question 853590: What is the sum of the infinite geometric series?
(-15)+ 0+ 15 +30+.....+195
Please show me step by step, thank you in advance! Answer by richwmiller(17219) (Show Source):
You can put this solution on YOUR website! This is not a geometric series.
An = a1 + (n - 1)d
195 = -15 + (14)15
and it has 15 terms
the difference is 15
195 is the 15th term starting with -15
It is a finite arithmetic series
S = ½(a1 + an)n
S = ½(-15 + 195)15
S = 90*15=1350
