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Find the sum of the following series to infinity: 10 − 9 + 8.1 − 7.29 + ... ∞

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प्रश्न

Find the sum of the following series to infinity:

10 − 9 + 8.1 − 7.29 + ... ∞

योग
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उत्तर

This infinite G.P has first term a = 10 and common ratio r = `-9/10 = -0.9`

Thus the sum of the infinite G.P will be:

10 - 9 + 8.9 - 7.29 +  ... ∞ = `"a"/(1-"r")` [Since |r| < 1]

= `10/(1-(-0.9))`

= `10/1.9`

= `100/19`

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अध्याय 20: Geometric Progression - Exercise 20.4 [पृष्ठ ३९]

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आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 20 Geometric Progression
Exercise 20.4 | Q 1.4 | पृष्ठ ३९

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