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For each geometric progressions find the...

For each geometric progressions find the common ratio 'r'. And then find `a_(n)`.
(i) `3,3/2, 3/4, 3/8`,……
(ii) `2,-6, 18, -54`
(iii) `-1,-3,-9, -27`,…..
(iv) `5,2, 4/5, 8/25`,…..

Text Solution

Verified by Experts

The correct Answer is:
(i) `r=1/2, a_(n) = 3(1/2)^(n-1)`,
(ii) `r=-3, a_(n) = 2(-3)^(n-1)`
(iii) r=3; `a_(n) =(-1)(3)^(n-1)`
(iv) `r= 2/5; a_(n) = 5(2/5)^(n-1)`
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