Cho
. Tọa độ của vectơ
là
A.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019461189912592652/obj2019461189912592652326121_images/obj2019461189912592652326121_img1.png)
B.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019461189912592652/obj2019461189912592652815621_images/obj2019461189912592652815621_img1.png)
C.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019461189912592652/obj2019461189912592652880610_images/obj2019461189912592652880610_img1.png)
D.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019461189912592652/obj2019461189912592652654719_images/obj2019461189912592652654719_img1.png)
Đáp án và lời giải
Đáp án:B
Lời giải:Phân tích:
Ta có:
.
Vậy đáp án đúng là B.
![img1](https://cungthi.online/upload/questionbank3/eduquestion/2019461189912592652/obj2019461189912592652939729_images/obj2019461189912592652939729_img1.png)