Question

Giúp em câu 16 với ạ

Answer 1

Đặt \(\overrightarrow{d}=\left(x;y;z\right)\Rightarrow\left\{{}\begin{matrix}\overrightarrow{a}.\overrightarrow{d}=x+y-2z\\\overrightarrow{b}.\overrightarrow{d}=2x-y+2z\\\overrightarrow{c}.\overrightarrow{d}=-2x+3y-2z\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}x+y-2z=4\\2x-y+2z=5\\-2x+3y-2z=7\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}x=3\\y=6\\z=\dfrac{5}{2}\end{matrix}\right.\)

\(\Rightarrow\overrightarrow{d}=\left(3;6;\dfrac{5}{2}\right)\)