\(\left\{{}\begin{matrix}M\in ox=>M\left(x_m;0\right)\\N\in Oy=>N\left(0;y_n\right)\end{matrix}\right.\)
\(\left\{{}\begin{matrix}MN=\sqrt{x_m^2+y_n^2}\\IN=\sqrt{1^2+\left(y_n-4\right)^2}\\IM=\sqrt{\left(x_m-1\right)^2+4^2}\end{matrix}\right.\)
\(\Delta_{IMN}\)cân tại I \(\Rightarrow\left\{{}\begin{matrix}MN^2=IN^2+IM^2\\IN=IM\end{matrix}\right.\)
\(\left\{{}\begin{matrix}x_m^2+y_n^2=1+\left(y_n-4\right)^2+\left(x_m-1\right)^2+16\\1+\left(y_n-4\right)^2=\left(x_m-1\right)^2+16\end{matrix}\right.\) \(\begin{matrix}\left(1\right)\\\left(2\right)\end{matrix}\)
(1) <=>\(x_n^2+y_n^2=1+y_n^2-8y_m+16+x_n^2-2x_m+1+16\)
\(8\left(y_n-4\right)=2-2x_m;\left(y_n-4\right)=\dfrac{1-x_m}{4}\)
(2) <=> \(1+\dfrac{\left(x_m-1\right)^2}{16}=\left(x_m-1\right)^2+16\)
vô nghiệm
