Q66.If the coefficient of the three successive terms in the binomial expansion of (1 + x)n are in the ratio 1 : 7 : 42, then the first of these terms in the expansion is (1) 9th (2) 6th (3) 8th (4) 7th
What This Question Tests
This question requires setting up and solving equations based on the given ratios of successive binomial coefficients to determine the starting term number in the expansion.
Concepts Tested
Formulas Used
Coefficient of (r+1)th term = nCr
nCr / nC(r-1) = (n-r+1)/r
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📋 Question Details
- Chapter
- Binomial Theorem
- Topic
- Coefficients of binomial expansion
- Year
- 2015
- Shift
- 10 Apr Online
- Q Number
- Q66
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 8: Binomial Theorem
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