phuonglien99

Giải pt:

           $\sqrt{x+1+\sqrt{x^{2}+2x}}=\frac{27\sqrt{2x}x^{2}}{8}$

Hệ phương trình:

$\left\{\begin{matrix} x^{3}+y^{3}+xy^{2}+x^{2}y+3x+3y=3x^{2}+3y^{2}+2xy+2 & \\3\sqrt{x-1} -x^{2}=2y-3\sqrt[3]{8-2y}+5 & \end{matrix}\right.$

Cho $\Delta ABC$

                             CMR: $\frac{\sum asinA}{\sum acosA}=\sum cotA$

                   Cho $\Delta ABC$ có: $a^{2}+b^{2}-c^{2}=4R^{2}$

                                  CMR: $\frac{tanAtanB+1}{tanAtanB-1}=tan^{2}C$

Hệ 1:

$\left\{\begin{matrix} x^{3}+6y^{2}-y^{3}+2x-14y=-12 & \\ \sqrt{3-x}+\sqrt{y-3}=x^{2}+y^{2}-10x-5y+22 & \end{matrix}\right.$

Hệ 2:

            $\left\{\begin{matrix} \left ( 4x^{2}+1 \right )x+\left ( y-1 \right )\sqrt{1-2y}=0 & \\4x^{2} +y^{2}+4x+2\sqrt{3-4x}=3 & \end{matrix}\right.$