Y^4-27y=0 решите уравнение, x^3+7x^2=18x и это

[latex]y^4-27y=0\\y(y^3-27)=0\\y(y-3)(y^2+3y+9)=0\\\\y_1=0;\\\\y-3=0\\y_2=3;\\\\y^2+3y+9=\\D:9-36=-27\ \textless \ 0;\\\\y=0; \; 3.\\\\\\x^3+7x^2=18x\\x(x^2+7x-18)=0\\\\x_1=0;\\\\x^2+7x-18=0\\D:49+72=121\\x_1,_2=\frac{-7\pm11}{2}, \\x_1=2; \qquad x_2=-9.\\\\x=0; \; 2;\; -9.[/latex]