31/3 . 91/9 . 271/27 . 811/ 81…..upto infinity =

(a)√27 (b)3√27

© 4√27 (d)none of these

the ans is (d)none of these

reson ::: the geneal term of series is << 10 + (1/3)ⁿ >> as n -> infinity, (1/3)ⁿ -> 0

as the series doesnot have product of 10 in denominator, the product of series shuld have multiple of 10 in ans

hence it is (d)

Approved

But ans. is (c)..