$$\left\{x\le8\right\}$$  

$$\left\{\frac{7}{2}\le x<8\right\}$$  

$$\left\{x\le5\right\}$$  

$$\left\{x\ge\frac{7}{2}\right\}$$  

$$\left\{-1<x≤0\right\}$$  

$$\left\{3≤x<4\right\}$$  

$$\left\{-1<x≤0\ \ atau\ 3≤x<4\right\}$$  

$$\left\{-1<x<4\right\}$$  

$$2\le x<7$$  

$$-3\le x\le2\ \ atau\ x\ge7$$  

$$2<x<7$$  

$$-3\le x\le2$$  

$$1\le x\le5$$  

$$x\le3$$  

$$1\le x\le3\ \ atau\ x\ge5$$  

$$3\le x\le5$$  

$$\left\{x\ :\ x\le1\right\}$$

$$\left\{x\ :\ -5\le x\le2\right\}$$

$$\left\{x\ :\ x\ \le-1\right\}$$

$$\left\{x\ :\ x\le-2\right\}$$

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