6,AX=ranka- 1
7, 1/ 15
8,
Unknown parameters or statistics
9. Processing method: The common factor k (k = 1, 2, 3...n) is extracted from line k, so it is proposed that the determinant after the common factor is a common determinant in linear algebra: the Vandermonde determinant, and the value of the corresponding coefficient determinant is not 0 directly, so the corresponding equation has only 0 solution.
The solution is K=2.
10,A 1 1 = A 12A- 1 = A6A- 1 = E2A- 1 = A- 1 = 1/det 1
A*={ 1/2
√3/2}
{-√3/2
1/2}