A.(a·C.b-(a·B.c B.b-(a·b/a·A.a C.a×b D.a+(a×B.×a
已知|a|=2,|b|=,且a?b=3,則|a×b|等于()
A.2 B. C.2 D.2
已知|a|=1,|b|=,且=π/4,則|a+b|等于:()
A.1 B.1+ C.2 D.