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Find the sum of the products of the corresponding terms of the sequences and2,4,8,16,32and128,32,8,2,12 - Mathematics

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प्रश्न

Find the sum of the products of the corresponding terms of the sequences `2, 4, 8, 16, 32 and 128, 32, 8, 2, 1/2`

योग
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उत्तर

The product of the corresponding terms of the sequence 2, 4, 8, 16, 32 and 128, 32, 8, 2, `1/2` is 2 × 128, 4 × 32, 8 × 8, 16 × 2, 32 × `1/ 2` or 256, 128, 64, 32, 16

First term of the geometric progression, a = 256

r = `128/256 = 1/2, "n" = 5`

∴ Sum = `(256[1 - (1/2)^5])/(1 - 1/2)`

= `256 xx 2 (1 - 1/32)`

= `256 xx 2 xx 31/32`

= 16 × 31

= 496

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अध्याय 9: Sequences and Series - Exercise 9.3 [पृष्ठ १९३]

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एनसीईआरटी Mathematics [English] Class 11
अध्याय 9 Sequences and Series
Exercise 9.3 | Q 19 | पृष्ठ १९३

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