vectơ MA +2 vectơ MB +3 vectơ MC -4 vectơ MD=k vectơ MI44/62c) MA→+2MB→+3MC→−4MD→=kMI→k=3, IA→=2AB→+3AC→−4AD→k=2, IA→=2AB→+3AC→−4AD→k=1, IA→=2AB→+3AC→−4AD→k=4, IA→=2AB→+3AC→−4AD→Giải thíchc) k=2, IA→=2AB→+3AC→−4AD→ Chọn B