A.X+2y-z-6=0 B.2x-Y=0 C.Y+2z=0 D.x+z=0
A.x+y+4z-3=0B.2x+y+z-3=0C.x+2y+z-19=0D.x+2y+4z-9=0
設α=i+2j+3k,β=i-3j-2k,與α、β都垂直的單位向量為()。
A.A B.B C.C D.D