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The fifth term of a G.P. is x, eighth term of a G.P. is y and eleventh term of a G.P. is z verify whether y2 = xz - Mathematics and Statistics

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प्रश्न

The fifth term of a G.P. is x, eighth term of a G.P. is y and eleventh term of a G.P. is z verify whether y2 = xz

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उत्तर

Let a be the first term and r be the common ratio of the G.P.

Then t5 = x, t8 = y and t11 = z

Using tn = arn–1, we get

ar5–1 = x, ar8–1 = y and ar11–1 = z

∴ ar4 = x, ar7 = y and ar10 = z

∴ y2 = (ar7)2 = a2r14

= (ar4)(ar10) = xz

Hence, y2 = xz

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Sequences and Series - Exercise 2.1 [पृष्ठ २७]

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