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[ngocanh29092000]

$\left\{\begin{matrix} x^{3}-y^{3}&-x^{2}y+xy^{2}&-2xy-x+y=0\\ \sqrt{x-y}= x^{3}-2x^{2}+y+2 \end{matrix}\right.$

Edited by Mikhail Leptchinski, 04-08-2015 - 14:08.

[vuagialong]

$\left\{\begin{matrix} x^{3}-y^{3}&-x^{2}y+xy^{2}&-2xy-x+y=0\\ \sqrt{x-y}= x^{3}-2x^{2}+y+2 \end{matrix}\right.$

$\left\{\begin{matrix} x^{3}-y^{3}-x^{2}y+xy^{2}-2xy-x+y=0(1)\\ \sqrt{x-y}= x^{3}-2x^{2}+y+2(2) \end{matrix}\right.$

pt(1) $\Leftrightarrow (x-y-1)(x^2+y^2)$ $\Rightarrow \begin{bmatrix} x-y-1=0\\ x^2+y^2=0 \end{bmatrix}$

$\Rightarrow \begin{bmatrix} x-y=0\\ x=0, y=0 \end{bmatrix}$

thay x-y=1 vào pt(2) $\Rightarrow x^3-2x^2+x$ vi $y=x-1$

làm nốt nhé 

Edited by vuagialong, 04-08-2015 - 10:57.