Q64.The sum to 20 terms of the series 2 ⋅22 −32 + 2 ⋅42 −52 + 2 ⋅62−. . . . . . . . . . . . is equal to __________.
What This Question Tests
This question requires identifying the pattern in a given series, expressing its general term, and then using standard summation formulas to calculate the sum of the first 20 terms.
Concepts Tested
Formulas Used
Σk² = n(n+1)(2n+1)/6
Σk = n(n+1)/2
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Sum of series
- Year
- 2023
- Shift
- 13 Apr Shift 1
- Q Number
- Q64
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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