Объяснение: -3≤2x-5≤3 2≤2x≤8 1≤x≤4
метод интервалов (x-4)(x+2)≥0 x∈(-∞;-2]∪[4;+∞)
5*4^x=320 4^x=64 x=3
1)
![|2x-5|\leq 3\\\\\left \{ {{2x-5\leq3 } \atop {2x-5\geq-3}} \right.\\\\\left \{ {{2x\leq8 } \atop {2x\geq2 }} \right. \\\\\left \{ {{x\leq4 } \atop {x\geq1 }} \right.\\\\Otvet:\boxed{x\in[1;4]}](/tpl/images/0672/9676/83574.png)
2)
x² - 2x - 8 ≥ 0
(x - 4)(x + 2) ≥ 0
+ - +
__________[- 2]__________[4]__________
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Otvet : x ∈ (- ∞ ; - 2] ∪ [4 ; + ∞)
3)
