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प्रश्न
Determine whether the sum to infinity of the following G.P.s exist, if exists find them:
`1/2, 1/4, 1/8, 1/16,...`
उत्तर
Here, a = `1/2`, r = `1/2`
Since | r | = `|1/2| = 1/2 < 1`, the sum to infinity of this G.P. exist and
S = `"a"/(1 - "r")`
= `((1/2))/(1 - 1/2)`
= `((1/2))/((1/2))`
= 1
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