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Задание 3862
Решите неравенство: $$\frac{3\log_{0,5}x}{2-\log_{0,5}x}\geq2\log_{0,5}x+1$$
$$\frac{3\log_{0,5}x}{2-\log_{0,5}x}\geq2\log_{0,5}x+1$$
ОДЗ: $$\left\{\begin{matrix}x>0\\\log_{0,5}x\neq2\end{matrix}\right.$$ $$\Leftrightarrow$$
$$\left\{\begin{matrix}x>0\\x\neq\frac{1}{4}\end{matrix}\right.$$
Пусть $$\log_{0,5}x=y$$
$$\frac{3y}{2-y}\geq2y+1$$
$$\frac{3y-(2y+1)(2-y)}{2-y}\geq0$$
$$\frac{3y-4y+2y^{2}-2+y}{2-y}\geq0$$
$$\frac{2y^{2}-2}{2-y}\geq0$$
$$\Leftrightarrow\frac{(y-1)(y+1)}{2-y}\geq0$$
$$\left\{\begin{matrix}y\leq-1\\\left\{\begin{matrix}y\geq1\\y<2\end{matrix}\right.\end{matrix}\right.$$
$$\left\{\begin{matrix}\log_{0,5}x\leq-1\\\left\{\begin{matrix}\log_{0,5}x\geq1\\\log_{0,5}x<2\end{matrix}\right.\end{matrix}\right.$$
$$\left\{\begin{matrix}x\geq2\\\left\{\begin{matrix}x\leq\frac{1}{2}\\x>\frac{1}{4}\end{matrix}\right.\end{matrix}\right.$$