Q76.The first two terms of a geometric progression add up to 12. The sum of the third and the fourth terms is 48. If the terms of the geometric progression are alternately positive and negative, then the first term is (1) −4 (2) −12 (3) 12 (4) 4
What This Question Tests
This question involves setting up and solving a system of equations based on the given sums of terms in a geometric progression, with an additional constraint about the alternating signs of the terms.
Concepts Tested
Formulas Used
a_n = ar^(n-1)
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Geometric Progression
- Year
- 2008
- Shift
- Unknown
- Q Number
- Q76
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
More from this Chapter
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