A B → = − 2 ; − 1 A C → = − 3 ; − 2 ⇒ A B → − A C → = − 2 − − 3 ; − 1 − − 2 = 1 ; 1 .

Đáp án B

\(\left\{{}\begin{matrix}\overrightarrow{AB}=\left(-2;-1\right)\\\overrightarrow{AC}=\left(-3;-2\right)\end{matrix}\right.\)

\(\Rightarrow\overrightarrow{AB}-\overrightarrow{AC}=\left(-2-\left(-3\right);-1-\left(-2\right)\right)=\left(1;1\right)\)

Chọn D

a: \(\left\{{}\begin{matrix}x_G=\dfrac{2+4+2}{3}=\dfrac{8}{3}\\y_G=\dfrac{1+0+3}{3}=\dfrac{4}{3}\end{matrix}\right.\)

\(\left\{{}\begin{matrix}x_I=\dfrac{2+4}{2}=3\\y_I=\dfrac{1+0}{2}=\dfrac{1}{2}\end{matrix}\right.\)

Chọn A

x I = 2 + 4 2 = 3 y I = − 3 + 7 2 = 2 ⇒ I 3 ; 2 .

Đáp án C

x I = 2 + 4 2 = 3 y I = − 3 + 7 2 = 2 ⇒ I 3 ; 2 .

Đáp án C