मराठी

For a, b, c to be in G.P. the value of a-bb-c is equal to ______.

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प्रश्न

For a, b, c to be in G.P. the value of `(a - b)/(b - c)` is equal to ______.

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उत्तर

For a, b, c to be in G.P. the value of `(a - b)/(b - c)` is equal to `a/b` or `b/c`.

Explanation:

Since a, b and c are in G.P

∴ `b/a = c/b` = r   .....(Constant)

⇒ b = ar and c = br

⇒ c = ar · r = ar2

So `(a - b)/(b - c) = (a - ar)/(ar - ar^2)`

= `(a(1 - r))/(ar(1 - r))`

= `1/r`

= `a/b`

= `b/c`

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पाठ 9: Sequences and Series - Exercise [पृष्ठ १६४]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
पाठ 9 Sequences and Series
Exercise | Q 27 | पृष्ठ १६४

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