Q83.If the constant term, in binomial expansion of (2xr + x21 ) 10 is 180, then r is equal to ____________.
What This Question Tests
This question assesses the ability to find the general term in a binomial expansion and then determine the condition for it to be a constant term, followed by solving for the unknown exponent.
Concepts Tested
Formulas Used
Tr+1 = nCr * a^(n-r) * b^r
📚 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.
2.2 — A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 · Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
3.23 — The Rate Constant For The Decomposition Of Hydrocarbons Is 2.418 × 10–5S–1
Chemistry Class 11 · Chapter 3
3.23 The rate constant for the decomposition of hydrocarbons is 2.418 × 10–5s–1 at 546 K. If the energy of activation is 179.9 kJ/mol, what will be the value of pre-exponential factor.
📋 Question Details
- Chapter
- Binomial Theorem
- Topic
- General term of binomial expansion
- Year
- 2021
- Shift
- 22 Jul Shift 1
- Q Number
- Q83
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 8: Binomial Theorem
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