We are given:
Step 1: Relationship between adjoint and determinant The adjoint of a matrix , denoted as , satisfies the following property: where is the identity matrix and is the determinant of . Given , we have:
Step 2: Properties of the adjoint matrix The adjoint matrix is the transpose of the cofactor matrix of . For the adjoint to be valid, the entries in must satisfy this relationship when multiplied with .
Step 3: Expand for consistency Matrix is symmetric, so it represents the adjoint matrix. For the adjoint to hold, the diagonal entries of must match the cofactors of , and off-diagonal entries must not affect the determinant calculation adversely. The symmetry of suggests ensures consistency with the determinant .
Conclusion: Thus, the value of is: ---