Q12.For positive integers n, if 4an = (n2 + 5n + 6) and Sn = โnk=1 ( ak1 ), then the value of (1) 540 (2) 675 (3) 1350 (4) 135
What This Question Tests
This question involves recognizing a pattern in the given term `a_n`, decomposing it using partial fractions, and then finding the sum of the series using a telescopic sum approach.
Concepts Tested
Formulas Used
Partial fraction decomposition: 1/(n(n+1)) = 1/n - 1/(n+1)
Summation notation ฮฃ
๐ NCERT Sections This Tests
8.17 โ Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 ยท Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
12.5 โ A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 ยท Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
2.2 โ A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 ยท Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
๐ Question Details
- Chapter
- Sequences & Series
- Topic
- Summation of series, Partial fractions
- Year
- 2025
- Shift
- 28 Jan Shift 2
- Q Number
- Q12
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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