Q78. x2 + x x + 1 x −2 If 2x2 + 3x −1 3x 3x −3 = ax −12 , then a is equal to: x2 + 2x + 3 2x −1 2x −1 (1) −24 (2) 24 (3) −12 (4) 12
What This Question Tests
The question requires evaluating a 3x3 determinant. A smart approach involves using column operations to simplify the determinant and then substituting a value for x to find 'a' efficiently.
Concepts Tested
Formulas Used
R_i -> R_i - R_j
Expansion along a column/row
📚 NCERT Sections This Tests
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.
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.
12.1 — (A) No Different From
Physics Class 12 · Chapter 12
12.1 (a) No different from (b) Thomson’s model; Rutherford’s model (c) Rutherford’s model (d) Thomson’s model; Rutherford’s model (e) Both the models
📋 Question Details
- Chapter
- Matrices & Determinants
- Topic
- Evaluation of Determinants
- Year
- 2015
- Shift
- 11 Apr Online
- Q Number
- Q78
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 4: Determinants
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