BA=B+2E则 B(A-E) = 2EB = 2(A-E)^-1A-E = 1 1-1 1(A-E)^-1 = 1/2 -1/2 1/2 1/2B = 2(A-E)^-1 =1 -11 1
似乎把你的答案除以二就行了，你再算一遍
