已知向量 a_1, a_2, a_3, a_4, a_5，且有 r(alpha _1, alpha _2, alpha _3, alpha _4)= 3，r(alpha _1, alpha _2, alpha _3, alpha _5)= 4，则 r(a_1, a_2, a_3, a_4 + a_5)= ()

19已知向量a_1,a_2,a_3,a_4,a_5,且有r(a_1,a_2,a_3,a_4)=3,r(a_1,a_2,a_3,a_5)=4,则r(a_1,a_2

已知向量a_1,a_2,a_3,a_4,a_5,且有r(a_1,a_2,a_3,a_4)=3,r(a_1,a_2,a_3,a_5)=4,则r(a_1,a_2,a

向量方程((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0，其中((a)_(1)+alpha )-7

若向量组(alpha )_(1),(alpha )_(2),(alpha )_(3)线性无关，则向量组(alpha )_(1),(alpha )_(2),(al

已知向量组alpha_(1),alpha_(2),alpha_(3)线性无关，证明：alpha_(1)+2alpha_(2),2alpha_(1)+3alpha

4.求向量组alpha_(1)=(1,1,2,3),alpha_(2)=(1,-1,1,1),alpha_(3)=(1,3,3,5),alpha_(4)=(4,

设向量组(alpha )_(1),(alpha )_(2),(alpha )_(3) 线性无关， (alpha )_(1),(alpha )_(2),(alph

设向量组 alpha_1, alpha_2, alpha_3, alpha_4, alpha_5秩为 3，且满足 alpha_1 + alpha_3 - a

已知向量组alpha_(1),alpha_(2),alpha_(3)线性无关，若alpha_(1)+alpha_(2),alpha_(2)+alpha_(3),

向量组 alpha_2, alpha_4, alpha_5 线性无关，则整体向量组 alpha_1, alpha_2, alpha_3, alpha_4, al