初等行变换即可r2-2r1，r3-3r1~1 λ λ 1 00 1-2λ 1-2λ 0 00 2-2λ 2-2λ 1 1 r3-r2~1 λ λ 1 00 1-2λ 1-2λ 0 00 1 1 1 1 r1-r3*λ，r2-r3*(1-2λ) 交换r2r3~1 0 0 1-λ -λ0 1 1 1 10 0 0 2λ-1 2λ-1
