5-λ2226-λ0204-λ= (4-λ)(5-λ)(6-λ)-4(6-λ)-4(4-λ)--直接对角线法则得= (4-λ)(5-λ)(6-λ)-4(10-2λ) --后两项合并得因子(5-λ)= (4-λ)(5-λ)(6-λ)-8(5-λ)= (5-λ)[(4-λ)(6-λ)-8]=...