Q81.Let a = 1 + 2C23! + 3C24! + 4C25! + … 1! + 2! + 3! + … Then 2b is equal to a2
What This Question Tests
This question involves evaluating two complex series, 'a' and 'b', which require manipulation of binomial coefficients and factorials before finding the value of the requested expression.
Concepts Tested
Formulas Used
nCr = n! / (r! * (n-r)!)
Σ nCr = 2^n
1/k! = (k+1-1)/k!
📚 NCERT Sections This Tests
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
3.18 — For A First Order Reaction, Show That Time Required For 99% Completion
Chemistry Class 11 · Chapter 3
3.18 For a first order reaction, show that time required for 99% completion is twice the time required for the completion of 90% of reaction.
8.17 — Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 · Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Summation of series
- Year
- 2024
- Shift
- 04 Apr Shift 1
- Q Number
- Q81
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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