Q65.The sum of the series: 1 + 1+21 + 1+2+31 + … …. upto 10 terms, is: (1) 18 (2) 22 11 13 (3) 20 (4) 16 11 9 2 15
What This Question Tests
This question requires identifying the general term of the series, which involves the sum of natural numbers in the denominator, and then summing the resulting terms using a telescoping technique.
Concepts Tested
Formulas Used
Σk = k(k+1)/2
Σ(1/(k(k+1))) = Σ(1/k - 1/(k+1))
📚 NCERT Sections This Tests
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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.
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1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
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📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Summation of series
- Year
- 2013
- Shift
- 09 Apr Online
- Q Number
- Q65
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences & Series
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