If A = [aij] is a 3 × 3 scalar matrix such that a11 = 2, then write the value of |A|.

Q14 of 256 Page 7

If A = [a_ij] is a 3 × 3 scalar matrix such that a₁₁ = 2, then write the value of |A|.

A scalar matrix is a matrix of order m which is equal to a constant λ multiplied with the Identity matrix of order m.

Since a₁₁=2, hence λ=2 and m=3

Hence

Then,

Expanding along R₁

|A|=2(2×2-0)

If and , find .

If A = [a_ij] is a 3 × 3 diagonal matrix such that a₁₁ = 1, a₂₂ = 2 and a₃₃ = 3, then find |A|.

If I₃ denotes identity matrix of order 3 × 3, write the value of its determinant.

A matrix A of order 3 × 3 has determinant 5. What is the value of |3A|?