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Question
Find the geometric means of the following pairs of number:
2 and 8
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Solution
\[\text { Let the G . M . between 2 and 8 be G } . \]
\[\text { Then, 2, G and 8 are in G . P } . \]
\[ \therefore G^2 = 2 \times 8\]
\[ \Rightarrow G^2 = 16\]
\[ \Rightarrow G = \pm \sqrt{16}\]
\[ \Rightarrow G = \pm 4\]
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