Chủ đề này có 1 trả lời

[Ilovethobong]

1. $\left | x-1 \right |+\left | -2x+6 \right |\geq x-5$

2.$\sqrt{-x^2+4x-3}\geq 2x-5$

3. $\left | x^2+x-1 \right |\leq 2x-1$

4.$\sqrt{-x^2+6x-5}\geq 8-2x$

[conankun]

1. $\left | x-1 \right |+\left | -2x+6 \right |\geq x-5$

2.$\sqrt{-x^2+4x-3}\geq 2x-5$

3. $\left | x^2+x-1 \right |\leq 2x-1$

4.$\sqrt{-x^2+6x-5}\geq 8-2x$

1. $\left | x-1 \right |+\left | -2x+6 \right |\geq \left | x-1-2x+6 \right | = \left | -x+5 \right |\geq x-5$

Dấu "=" xảy ra khi: $\left\{\begin{matrix} (x-1)(-2x+6)\geq 0\\ x\geq 5 \end{matrix}\right.$.....