Question

1) Cho duong thang Δ : \(\left\{{}\begin{matrix}x=1+t\\y=2-t\\z=1+2t\end{matrix}\right.\)

Viet phuong trinh duong thang d di qua A (1;1;1) cat va vuong goc voi Δ

Answer 1

\(\overrightarrow{u}=\left(1;-1;2\right)\)  ;  A(1;1;1) \(\Rightarrow\left\{{}\begin{matrix}1+t\\1-t\\1+2t\end{matrix}\right.\)