矩阵A是4x4阶的矩阵A=[a 1 1 1/1 a 1 1/1 1 a 1/1 1 1 a],r(A)=3,a=?
问题描述:
矩阵A是4x4阶的矩阵A=[a 1 1 1/1 a 1 1/1 1 a 1/1 1 1 a],r(A)=3,a=?
答
r1-r2,r2-r3,r3-r4a-1 1-a0 0 0a-1 1-a0 0 0a-1 1-a 1 1 1 a若 a=1 则 R(A) = 1. 故a≠1.第1,2,3行乘 1/(a-1) 1-10 0 0 1-10 0 0 1-1 1 1 1 ar3-r1-2r2-3r3 1-10...最後r3-r1-2r2-3r3 1-10 0 0 1-10 0 0 1-1 0 0 0 a+3其實是不是r4-r1-2r2-3r3才對?