Charles007
Sep1-09, 07:53 PM
I know how to find the adjugate of 3x3 matrix. from the defination.
How to find adjugate of 2x2 matrix.
e.g A= ( 1 3 )
______( 2 4 )
adjoint .
First . we find matrix of cofactor. from the defination. (n-1)(n-1) matrix * (sign associated with the element's position).
Second, we taking the transpose we get the adj(A)
Then we find the det(A).
Finally, A^-1 = 1/det(A) * adj(A)
The inverse of A.
AA^- = A^-A=I and A adj(A) = det(A)I
The inverse of A = det(A)I/ A^-
How to find adjugate of 2x2 matrix.
e.g A= ( 1 3 )
______( 2 4 )
adjoint .
First . we find matrix of cofactor. from the defination. (n-1)(n-1) matrix * (sign associated with the element's position).
Second, we taking the transpose we get the adj(A)
Then we find the det(A).
Finally, A^-1 = 1/det(A) * adj(A)
The inverse of A.
AA^- = A^-A=I and A adj(A) = det(A)I
The inverse of A = det(A)I/ A^-