Question

If adj A=(2 - 4 2 find A
- 3 12 - 7
- 2 0 2)

Answer 1

Answer:

Given, A=[

5

7

2

3

]

Therefore,

∣A∣=

∣

∣

∣

∣

∣

∣

5

7

2

3

∣

∣

∣

∣

∣

∣

=15−14=1

We know that, |adj (A)| = ∣A∣

n−1

, where n is order of determinant.

Therefore,

∣adj(A)∣=∣1∣

2−1

∣adj(A)∣=1