向量方程((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0，其中((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0，则((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0A ((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0B ((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0C ((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0D ((a)_(1)+alpha )-7((alpha )_(2)+alpha )+4(alpha )_(3)=0

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

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，其中 alpha_1, alpha_2, alpha_3 线性无关，则必有（）A

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(a

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

设向量组alpha_(1)=(1,-1,2,4),alpha_(2)=(0,3,1,2),alpha_(3)=(3,0,7,14),alpha_(4)=(1,-

设矩阵 =((alpha )_(1),(alpha )_(2),(alpha )_(3),(beta )_(1))，=((alpha )_(1),(alpha

设 alpha (alpha )_(1),(alpha )_(2),(alpha )_(3),(beta )_(1),(beta )_(2) 均为四维列向量矩阵

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

七、证明:如果向量组(alpha )_(1),(alpha )_(2),(alpha )_(3)线性无关,则向量组(alpha )_(1),(alpha )_(