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📐 Mathematics  ·  Matrices  ·  JEE

For a 3x3 matrix A, det(2A) =

Answer: 8 det(A).

  • A 2 det(A)
  • B 4 det(A)
  • C 6 det(A)
  • D 8 det(A)

Correct answer: D. 8 det(A)

Explanation: det(kA) = k<sup>n</sup> det(A) for an n x n matrix. For 3x3: det(2A) = 2<sup>3</sup> det(A) = 8 det(A).

Matrix A (3 rows x 3 columns)a11a12a13a21a22a23a31a32a33column 1column 2column 3row 1row 2row 3

Element aij of matrix A sits at the intersection of row i and column j.

Concept context

Matrix operations, determinants, inverses, and solving linear systems

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