题目

若a=(0,1,-1),b=(1,1,0),且(a+λb)⊥a,则实数λ的值是A.-1                             B.0                              C.1                              D.-2 答案：答案：D解析:a+λb=(0,1,-1)+(λ,λ,0)=(λ,1+λ,-1).由(a+λb)⊥a,知(a+λb)·a=0.所以λ×0+(1+λ)×1-1×(-1)=0,解得λ=-2.

查看本题答案和解析