Question

Answer 1

Bài 1 :

a) Góc giữa \(\left(\overrightarrow{AB};\overrightarrow{CD}\right)=180^o\)

b) Góc giữa \(\left(\overrightarrow{AB};\overrightarrow{NC}\right)=0^o\)

c) Góc giữa \(\left(\overrightarrow{AD};\overrightarrow{NM}\right)=90^o+45^o=135^o\)

d) Góc giữa \(\left(\overrightarrow{BA};\overrightarrow{MC}\right)=90^o\)

Bài 3 

a) Góc giữa \(\left(\overrightarrow{AB};\overrightarrow{AC}\right)=60^o\)

b) Góc giữa \(\left(\overrightarrow{AB};\overrightarrow{CN}\right)=120^o\)

c) Góc giữa \(\left(\overrightarrow{AM};\overrightarrow{CM}\right)=120^o+30^o=150^o\)

d) Góc giữa \(\left(\overrightarrow{AB};\overrightarrow{MN}\right)=180^o\)

e) Góc giữa \(\left(\overrightarrow{MN};\overrightarrow{NC}\right)=120^o\)