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Question
The third term of G.P. is 4. The product of its first 5 terms is ______.
Options
43
44
45
None of these
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Solution
The third term of G.P. is 4. The product of its first 5 terms is 45.
Explanation:
Given that T3 = 4
⇒ ar3–1 = 4
⇒ ar2 = 4
Product of first 5 terms = a · ar · ar2 · ar3 · ar4
= a5r10
= (ar2)5
= (4)5
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