Q69.Let A be a 3 ร 3 matrix with det (A) = 4. Let Ri denote the ith row of A . If a matrix B is obtained by performing the operation R2 โ2R2 + 5R3 on 2 A , then det (B) is equal to : (1) 64 (2) 16 (3) 128 (4) 80
What This Question Tests
This question tests the understanding of how determinant values change when a matrix is scaled and when elementary row operations are performed.
Concepts Tested
Formulas Used
det(kA) = k^n det(A)
det(B) = det(A) if R_i -> R_i + kR_j
det(B) = k det(A) if R_i -> kR_i
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๐ Question Details
- Chapter
- Determinants
- Topic
- Properties of determinants
- Year
- 2021
- Shift
- 25 Feb Shift 2
- Q Number
- Q69
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 4: Determinants
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