Question

heya mate☺

1.If A is a square matrix of order 2 then find the value of |A|+|-A|.

2.If A be a square matrix of order2 whose determinant is -i,find the value of |A(adjA)|.

✌anyone please answer this question correctly don't unnecessary answer✔​

Answer 1

Answer:

1) 2 | A |

2) | A ( adj A ) | = - 1

Step-by-step explanation:

Solution-----> Plzzz refer the attachment

2) In 2nd question we use ,

A ( adj A ) = | A | I , and then putting | A | = - i

and using i² = - i

Additional information----->

1) If A⁻¹ is inverse of A then

A A⁻¹ = A⁻¹ A = I

Where I is identity matrix

2) If A and B are two non singular matrices of same order then AB is also a non singular matrix and

( AB )⁻¹ = B⁻¹ A⁻¹

Answer 2

Q.2

If A be a square matrix of order2 whose determinant is -i,find the value of |A(adjA)|.

for any square matrix A of order 'n'

|Aadj(A)| = |A|^n

here |A| = det (A)

for this case n = 2 and |A| = -1

therefore,

|A.adj (A)| = (-1)² = 1

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wish u best for exam...❤

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