Q71.For a positive integer n, (1 + x ) is expanded in increasing powers of x . If three consecutive coefficients in this expansion are in the ratio, 2 : 5 : 12, then n is equal to
What This Question Tests
This question tests the understanding of the ratio property of consecutive binomial coefficients and solving the resulting system of two linear equations to find the value of n.
Concepts Tested
Formulas Used
nCr / nC(r-1) = (n-r+1)/r
nCr
📚 NCERT Sections This Tests
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
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.
📋 Question Details
- Chapter
- Binomial Theorem
- Topic
- Properties of binomial coefficients
- Year
- 2020
- Shift
- 02 Sep Shift 2
- Q Number
- Q71
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 8: Binomial Theorem
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