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Question
Find the next three terms of the sequence :
`sqrt5, 5, 5sqrt(5), .............`
Solution
Given sequence: `sqrt5, 5, 5sqrt(5), .............`
Now,
`5/sqrt5 = sqrt5, (5sqrt5)/5 = sqrt(5)`
Since `5/sqrt5 = (5sqrt5)/52 = .......... = sqrt(5)`, the given sequence is a G.P. with first term, a = `sqrt(5)` and common ratio, r = `sqrt(5)`
Now, Tn = arn – 1
∴ Next three term:
4th term = `sqrt(5) xx (sqrt5)^3`
= `sqrt(5) xx 5sqrt(5)`
= 25
5th term = `sqrt(5) xx (sqrt5)^4`
= `sqrt(5) xx 25`
= `25sqrt(5)`
6th term = `sqrt(5) xx (sqrt5)^5`
= `sqrt(5) xx 25sqrt(5)`
= 125
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