Question

Adjoint of each of the matrices `[(1, 2),(3, 4)]` is

विकल्प

• `[(4, -2),(-3, 1)]`

• `[(1, 2),(3, 4)]`

• `[(-3, -4),(-1, -2)]`

• Zero

Answer 1

`[(4, -2),(-3, 1)]`

Explanation:

Let A = `[(4, -2),(-3, 1)]`

Since cofactor of `a_(ij)` is A_i = `(-1)^(i + 1)M_(Li)`

Then, A₁₂ = 4, A₂ = – 3, A₂₁ = – 2, A₂₂ = 1

Adj A = `[(A_11, A_21),(A_12, A_22)] = [(4, -2),(-3, 1)]`