alpha =(1,a,0), beta =(-1,2,b), 欲使 alpha +beta =0, 则 ()-|||-A、 =2, b=0 B、 a=-2 b=0-|||-C、 =0, b=2 D、 =0, b=-2

6.设α1,α2,α3线性无关, (beta )_(1)=a(alpha )_(1)+b(alpha )_(2) (beta )_(2)=a(alpha )_(

设向量0 1 2-|||-(alpha )_(1)= 1 _(2)= 1 ,beta = 1-|||--1 1 3，则0 1 2-|||-(alpha )_(1

(α>0,β>0).若f`(x)在 x=0 处连续,则-|||-(A) alpha -beta gt 1. (B) lt alpha -beta leqslan

1.“sin^2 alpha +sin^2 beta =1”是“sin alpha +cos beta =0”的（）.A. 充分非必要条件B. 必要非充分条件C

若3 0 0-|||-A= 0 a b-|||-0 2 3与3 0 0-|||-A= 0 a b-|||-0 2 3相似，则（ ）.(A)a=0,b=

8.若向量组α1,α2,α3线性无关, (beta )_(1)=(alpha )_(1)-(alpha )_(2), (beta )_(2)=(alpha )_

8.设向量alpha_(1)=(1,0,-2)^T，alpha_(2)=(0,0,1)^T，向量beta是alpha_(1),alpha_(2)的线性组合，则下

( 1 ) 求 _(1)=((-1,2,1))^T (beta )_(2)=((1,0,b))^7的值 ; ( 2 ) 写出_(1)=((-1,2,1))^T

1 设 -|||-A、 α,β.-|||-B、 α,β,y:-|||-C、 alpha +beta ;-|||-D、 alpha -beta ;

已知alpha_(1),alpha_(2),beta,gamma均为3维列向量，又A=(alpha_(1),alpha_(2),beta)，B=(alpha_(