Rút gọn:

\(A=\left(\dfrac{2x-1+\sqrt{x}}{1-x}+\dfrac{2x\sqrt{x}+x-\sqrt{x}}{1+x+\sqrt{x}}\right).\dfrac{\left(x-\sqrt{x}\right)\left(1-\sqrt{x}\right)}{2\sqrt{x}-1}-1\)

Giải hệ pt:

\(\left\{{}\begin{matrix}x^2+2y^2+3xy+3=0\\\dfrac{x-y+18}{\left(x+y\right)^2}=9\sqrt{x-y}\end{matrix}\right.\)

Giải hệ pt:

\(\left\{{}\begin{matrix}x^2+1+xy+y^2-4y=0\\\left(x^2+1\right)\left(x+y-2\right)=y\end{matrix}\right.\)

Giải hệ pt: (Em xin lỗi vì bài trước em ghi sai đề:() 

\(\left\{{}\begin{matrix}x^3+y^3+3xy=1\\\sqrt{\left(4-x\right)\left(13-y\right)}=\dfrac{2x+3y+25}{2x+y+2}\end{matrix}\right.\)

Giải hệ pt:

\(\left\{{}\begin{matrix}x^3+y^3+3xy=1\\\sqrt{\left(4-x\right)\left(13-y\right)}=\dfrac{2x+2y+25}{2x+y+2}\end{matrix}\right.\)

Giải pt:

\(\left(3x^2+4x-4\right)\sqrt{x-1}=x\left(x^2-3x+3\right)\)

Giải pt:

\(\left(22x-3x^2-4\right)\sqrt{x-1}=x\left(3x-x^2-3\right)\)

Giải hệ pt:

\(\left\{{}\begin{matrix}1+6y=\dfrac{x}{y}-\sqrt{x-y}\\x+\sqrt{3y-1}=y+\sqrt{x-y}\end{matrix}\right.\)