(a1a2)(b1b2)
(a1a2)(b1b2)=(a1b1a2b1a1b2a2b2)
只要证明
(ACBD)(EGFH)=(AE+BGCE+DGAF+BHCF+DH)
即可,
(a11a21a12a22)(b11b21b12b22)=(()⋅()()⋅()()⋅()()⋅())