Question

развяжите систему уравнений

Answer 1

$\left \{ {{3^{x}+3^{y}=12} \atop {x+y=3}} \right.\\\\\left \{ {{x=3-y} \atop {3^{3-y}+3^{y}=12}} \right.\\\\\left \{ {{x=3-y} \atop {27*3^{-y}+3^{y}=12}} \right.\\\\3^{y}=m,m>0\\\\27*\frac{1}{m}+m-12=0\\\\\frac{m^{2}-12m+27 }{m}=0\\\\\left \{ {{m^{2}-12m+27=0 } \atop {m\neq0 }} \right.\\\\m_{1} =3\\\\m_{2}=9\\\\1)3^{y}=3\\\\y_{1}=1\\\\x_{1}=3-1=2\\\\2)3^{y}=9\\\\3^{y}=3^{2}\\\\y_{2}=2\\\\x_{2}=3-2=1 \\\\Otvet:\boxed{(1,2),(2;1)}$