Q66.The value of r for which 20Cr20C0 + 20Cr−120C1 + 20Cr−220C2 + … + 20C020Cr is maximum, is: (1) 15 (2) 20 (3) 11 (4) 10
What This Question Tests
This problem involves identifying the sum of products of binomial coefficients as a form of Vandermonde's Identity and then finding the value of r for which this sum is maximized.
Concepts Tested
Formulas Used
nCr = nC(n-r)
Σ(nCr * nC(k-r)) = (2n)Ck
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Permutation & Combination
- Topic
- Properties of binomial coefficients
- Year
- 2019
- Shift
- 11 Jan Shift 1
- Q Number
- Q66
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
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