Q66.If 1 + x4 + x5 = ∑5i=0 ai (1 + xi), for all x in R, then a2 is: (1) −4 (2) 6 (3) −8 (4) 10 is expanded in the ascending powers of x and the coefficients of powers of x in two consecutive
What This Question Tests
This question involves identifying a series that resembles an Arithmetic-Geometric Progression (AGP), finding its sum, and then determining the least integer 'n' that satisfies the given inequality. The series is subtly incorrect, leading to a modified GP sum.
Concepts Tested
Formulas Used
S_n = a/(1-r) for infinite GP if |r|<1
Sum of AGP S_n = a/(1-r) + dr/(1-r)^2 * (1 - r^(n-1) - (n-1)r^(n-1)(1-r))
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📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Sum of Geometric Progression (GP) and Arithmetic-Geometric Progression (AGP)
- Year
- 2014
- Shift
- 12 Apr Online
- Q Number
- Q66
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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