Question

\(\left\{{}\begin{matrix}\frac{2}{x}-3y^2=13\\\frac{3}{x}+y^2=14\end{matrix}\right.\)

Answer 1

\(\left\{{}\begin{matrix}\frac{2}{x}-3y^2=13\\\frac{3}{x}+y^2=14\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}\frac{2}{x}-3y^2=13\\\frac{9}{x}+3y^2=42\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}\frac{2}{x}+\frac{9}{x}=55\\y^2=14-\frac{3}{x}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\frac{11}{55}\\y^2=14-\frac{3}{x}\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=\frac{1}{5}\\y^2=14-3:\frac{1}{5}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\frac{1}{5}\\y^2=-1\end{matrix}\right.\)

Mà y² ≥ 0 ⇒ pt vô nghiệm