Answer:
146.41
Step-by-step explanation:
third order determinant = determinant of 3×3 matrix A
given ∣A∣=11
det (cofactor matrix of A) =set (transpare of cofactor amtrix of A) (transpare does not change the det)
=det(adjacent of A)
{det (cofactor matrix of A)} ^2 = {det (adjacent of A)}
^2
(Using for an n×n det (cofactor matrix of A)=det (A)^n−1
)
we get
det (cofactor matrix of A)^2 = {det(A) ^3−1
}^2
=(11)^2×2 = 11^4
=146.41
