Verification: 817-279-913 can be divisible by 45

Verification: 817-279-913 can be divisible by 45

It is proved that the original formula = 914-99 × 39-913 = 328-327-326 = 326 (32-3-1) = 326 × 5 = 324 × 32 × 5 = 45 × 324, so it can be divisible by 45

x^（n-2)+x^(n-4) ………… Factorization over real number field

x^（n-2)+x^(n-4)
=x^(n-4) (x^2+1)
Real number field is like this, high school (after learning imaginary number) can also be decomposed Oh!

Let a be a real symmetric matrix of order n and p be an invertible matrix of order n. given that the n-dimensional column vector α is the eigenvector of a belonging to the eigenvalue λ, then the eigenvector of the matrix (p-1ap) t belonging to the eigenvalue λ is ()
A. P-1αB. PTαC. PαD. （P-1）Tα

It is known that the n-dimensional column vector α is the eigenvector of a belonging to the eigenvalue λ, then: a α = λ α, (p-1ap) t = PTA (PT) - 1, both sides of the equation are multiplied by Pt α, that is: (p-1ap) t (PT α) = PTA [(PT) - 1pt] α = PTA α = λ (PT α), so select: B