Solve each of the following in equations and represent the solution set on the number line.
$\frac{1}{2-|x|} \geq$ $1, x \in R-\{-2,2\}$
Given:
$\frac{1}{2-|x|} \geq 1, x \in \mathrm{R} .-\{-2,2\}$
Intervals of $|x|:$
$x \geq 0,|x|=x$ and $x<0,|x|=-x$
Domain of $\frac{1}{2-|x|} \geq_{1}$
$\frac{1}{2-|x|} \geq 1$ is undefined at $x=-2$ and $x=2$
Therefore, Domain: $x<-2$ or $x>2$
Combining intervals with domain:
$x<-2,-2
For $x<-2$
$\frac{1}{2-(-x)} \geq 1$
Subtracting 1 from both the sides
$\frac{1}{2+x}-1 \geq_{1-1}$
$\frac{1-(2+x)}{2+x} \geq 0$
$\frac{1-2-x}{2+x} \geq 0$
$\frac{-1-x}{2+x} \geq 0$
Signs of $-1-x$ :
$-1-x=0 \rightarrow x=-1$
(Adding 1 to both the sides and then dividing by -1 on both the sides)
$-1-x>0 \rightarrow x<-1$
(Adding 1 to both the sides and then multiplying by -1 on both the sides)
$-1-x<0 \rightarrow x>-1$
(Adding 1 to both the sides and then multiplying by -1 on both the sides)
Signs of 2 + x:
$2+x=0 \rightarrow x=-2$ (Subtracting 2 from both the sides)
$2+x>0 \rightarrow x>-2$ (Subtracting 2 from both the sides)
$2+x<0 \rightarrow x<-2$ (Subtracting 2 from both the sides)
Intervals satisfying the required condition: ≥ 0
$-2 Merging overlapping intervals: $-2 Combining the intervals: $-2 Merging the overlapping intervals: No solution Similarly, for $-2 $\frac{1}{2-(-x)} \geq 1$ Therefore, Intervals satisfying the required condition: ≥ 0 $-2 Merging overlapping intervals: $-2 Combining the intervals: $-2 Merging the overlapping intervals: $-2 For $0 \leq x<2$ $\frac{1}{2-x} \geq 1$ Subtracting 1 from both the sides $\frac{1}{2-x}-1 \geq_{1-1}$ $\frac{1-(2-x)}{2-x} \geq 0$ $\frac{1-2+x}{2+x} \geq 0$ $\frac{x-1}{2+x} \geq 0$ Signs of x -1: $x-1=0 \rightarrow x=1$ (Adding 1 to both the sides) $x-1>0 \rightarrow x>1$ (Adding 1 to both the sides) $x-1<0 \rightarrow x<1$ (Adding 1 to both the sides) Signs of 2 + x: $2+x=0 \rightarrow x=-2$ (Subtracting 2 from both the sides) $2+x>0 \rightarrow x>-2$ (Subtracting 2 from both the sides) $2+x<0 \rightarrow x<-2$ (Subtracting 2 from both the sides) Intervals satisfying the required condition: ≥ 0 $1 Merging overlapping intervals: 1 ≤ x < 2 Combining the intervals: $1 \leq x<2$ and $0 \leq x<2$ Merging the overlapping intervals: $1 \leq x<2$ Similarly, for $x>2$ : $\frac{1}{2-x} \geq 1$ Therefore Intervals satisfying the required condition: ≥ 0 1 < x < 2 or x = 1 Merging overlapping intervals: 1 ≤ x < 2 Combining the intervals: 1 ≤ x < 2 and x > 2 Merging the overlapping intervals: No solution. Now, combining all the intervals: No solution or $-2 Merging the overlapping intervals: -2 < x ≤ 1 or 1 ≤ x < 2 Thus, $x \in(-2,-1] \cup[1,2)$