Q66.If for positive integers r > 1, n > 2, the coefficients of the (3r)th and (r + 2)th powers of x in the expansion of (1 + x)2n are equal, then n is equal to: (1) 2r + 1 (2) 2r −1 (3) 3r (4) r + 1
What This Question Tests
This question tests the understanding of binomial coefficients and their properties, specifically the symmetry property nCr = nC(n-r).
Concepts Tested
Formulas Used
n C k
n C x = n C y => x = y or x + y = n
📚 NCERT Sections This Tests
5.28 — How Many Ions Are Produced From The Complex Co(Nh3)6Cl2 In Solution?
Chemistry Class 11 · Chapter 5
5.28 How many ions are produced from the complex Co(NH3)6Cl2 in solution? (i) 6 (ii) 4 (iii) 3 (iv) 2 139 Coordination Compounds Reprint 2025-26
5.11 — Draw All The Isomers (Geometrical And Optical) Of:
Chemistry Class 11 · Chapter 5
5.11 Draw all the isomers (geometrical and optical) of: (i) [CoCl2(en)2] + (ii) [Co(NH3)Cl(en)2] 2+ (iii) [Co(NH3)2Cl2(en)]+
5.19 — [Cr(Nh3)6] 3+ Is Paramagnetic While [Ni(Cn)4] 2– Is Diamagnetic. Explain Why?
Chemistry Class 11 · Chapter 5
5.19 [Cr(NH3)6] 3+ is paramagnetic while [Ni(CN)4] 2– is diamagnetic. Explain why? 5.20 A solution of [Ni(H2O)6] 2+ is green but a solution of [Ni(CN)4] 2– is colourless. Explain. 5.21 [Fe(CN)6] 4– and [Fe(H2O)6] 2+ are of different colours in dilute solutions. Why?
📋 Question Details
- Chapter
- Binomial Theorem
- Topic
- Binomial coefficients
- Year
- 2013
- Shift
- 25 Apr Online
- Q Number
- Q66
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 8: Binomial Theorem
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