Q53.The sum of the first three terms of G. P is S and their products is 27 . Then all such S lie in (1) (−∞, −9] ∪[3, ∞) (2) [−3, ∞) (3) (−∞, −3] ∪[9, ∞) (4) (−∞, 9]
What This Question Tests
This question combines properties of geometric progression with inequalities related to the sum of a number and its reciprocal (x+1/x) to determine the range of possible sums.
Concepts Tested
Formulas Used
a/r, a, ar as GP terms
x+1/x ≥ 2 for x>0
x+1/x ≤ -2 for x<0
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📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Geometric Progression
- Year
- 2020
- Shift
- 02 Sep Shift 1
- Q Number
- Q53
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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