CHO A A. (2; 2; –1) B. (6; 0; 1) C. (5; 2; –2) D. (6; 4; –2)

Câu 3: Cho a 

A. (2; 2; –1) B. (6; 0; 1) C. (5; 2; –2) D. (6; 4; –2)