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Question
Determine whether the sum to infinity of the following G.P.s exist, if exists find them:
`1/5, (-2)/5, 4/5, (-8)/5, 16/5, ...`
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Solution
`1/5, (-2)/5, 4/5, (-8)/5, 16/5, ...`
`"a" = 1/5, "r" = ((-2)/5)/(1/5)` = – 2
Since, | r | = | – 2 | > 1
∴ Sum to infinity does not exist.
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