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Show that the products of the corresponding terms of the sequences a, ar, ar2, …arn – 1 and A, AR, AR2, … ARn-1 form a G.P, and find the common ratio

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प्रश्न

Show that the products of the corresponding terms of the sequences a, ar, ar2, …arn – 1 and A, AR, AR2, … `AR^(n-1)` form a G.P, and find the common ratio

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उत्तर

% Sequence a, ar, ar2, …. The sequence formed by the product of arn – 1 and the corresponding terms of A, AR, AR2, .... ARn – 1

`("Second term")/("First term")` = `(arAR)/(aA) = rR`

`("Third term")/("Second term")` = `(ar^2 AR^2)/(arAR) = rR`

Thus, the above sequence forms a G.P. and the common ratio is rR.

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अध्याय 8: Sequences and Series - EXERCISE 8.2 [पृष्ठ १४६]

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एनसीईआरटी Mathematics [English] Class 11
अध्याय 8 Sequences and Series
EXERCISE 8.2 | Q 20. | पृष्ठ १४६

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