$$ 设 $\overrightarrow{a}\ \ = \{ 3, 5, -2\}$,$\overrightarrow{b}\ \ = \{ 2, 1, 4\}$,且已知 $\lambda \overrightarrow{a}\ \ + \mu \overrightarrow{b}$与 z 轴垂直,则有 ()。 $$
设overrightarrow(a)=(-1,1,2),overrightarrow(b)=(2,-2,-4),则向量|overrightarrow(a)×ov
设overrightarrow(a)=(1,-1,2),overrightarrow(b)=(3,-2,-1),则overrightarrow(a)×overr
设overrightarrow(a)=(1,1,4),overrightarrow(b)=(1,-2,2),则overrightarrow(a)+overrig
[题目]设 |overrightarrow (a)|=3,, |overrightarrow (b)|=4,, |overrightarrow (c)|=5,
设 overrightarrow(a) = (2, -3, 2), overrightarrow(b) = (-4, 6, 4), 则 cos(overrigh
已知|overrightarrow(a)•overrightarrow(b)|=3,|overrightarrow(a)×overrightarrow(b)|=
已知|overrightarrow(a)|=2,|overrightarrow(b)|=sqrt(3),overrightarrow(a)与overrighta
设未知向量 overrightarrow(x)与 overrightarrow(a) = (2, -1, 2)共线,且满足 overrightarrow(a)
已知向量overrightarrow(a)=(0,1),overrightarrow(b)=(2,x),若overrightarrow(b)⊥(overrigh
[题目]设 |overrightarrow (a)|=4 |overrightarrow (b)|=3 , langle overrightarrow (a),