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Find the Geometric Means of the Following Pairs of Number: −8 and −2 - Mathematics

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Question

Find the geometric means of the following pairs of number:

−8 and −2

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Solution

\[\text {  Let the G . M . between - 8 and - 2 be G } . \]

\[\text { Then, - 8, G and - 2 are in G . P } . \]

\[ \therefore G^2 = \left( - 8 \right)\left( - 2 \right)\]

\[ \Rightarrow G^2 = 16\]

\[ \Rightarrow G = \pm \sqrt{16}\]

\[ \Rightarrow G = 4, - 4\]

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Chapter 20: Geometric Progression - Exercise 20.6 [Page 55]

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RD Sharma Mathematics [English] Class 11
Chapter 20 Geometric Progression
Exercise 20.6 | Q 4.3 | Page 55

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