हिंदी

If a, b, c are three consecutive terms of an A.P. and x, y, z are three consecutive terms of a G.P. Then prove that xb – c. yc – a . za – b = 1

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प्रश्न

If a, b, c are three consecutive terms of an A.P. and x, y, z are three consecutive terms of a G.P. Then prove that xb – c. yc – a . za – b = 1

योग
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उत्तर

We have a, b, c as three consecutive terms of A.P.

Then b – a = c – b = d   ...(say)

c – a = 2d

a – b = – d

Now xb – c . yc – a . za – b = x–d . y2d . z–d

= `x^(-d) (sqrt(xz))^(2d) * z^(-d)`  ....`("Since"  y = (sqrt(xz)))  "as"  x, y, z  "are"  "G.P.")`

= `x^(-d) * x^d * z^d * z^(-d)`

= `x^(-d + d) * z^(d - d)`

= `x^o z^o` = 1

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अध्याय 9: Sequences and Series - Solved Examples [पृष्ठ १५६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 9 Sequences and Series
Solved Examples | Q 12 | पृष्ठ १५६

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