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Question
Find the geometric means of the following pairs of number:
−8 and −2
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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