SOLUTION: Express 1-1/3+1/9-1/27...+(-1)^n(1/3^n)+... in scientific notation

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Question 1104777: Express 1-1/3+1/9-1/27...+(-1)^n(1/3^n)+... in scientific notation
Answer by greenestamps(13215) About Me  (Show Source):
You can put this solution on YOUR website!


This is an elementary infinite geometric series; the sum is a%2F%281-r%29 where a is the first term and r is the common ratio between terms.

S+=+1%2F%281-%28-1%2F3%29%29+=+1%2F%284%2F3%29+=+3%2F4

The sum is 3/4; it seems strange you would be asked to write that in scientific notation....

3/4 = 0.75 = 7.5x10^-1