[tex]\it I)\ x\in(-\infty,\ \ 0] \Rightarrow ecua\c{\it t}ia\ devine:\\ \\ -x-x+1=1 \Rightarrow -2x=0 \Rightarrow x=0 \Rightarrow S_1=\{0\}\\ \\ II)\ x\in(0,\ \ 1)\Rightarrow ecua\c{\it t}ia\ devine:\\ \\ x-x+1=1 \Rightarrow 0x=0 \Rightarrow S_2=(0,\ \ 1)\\ \\ III)\ x\in[1,\ \infty)\Rightarrow ecua\c{\it t}ia\ devine:\\ \\ x+x-1=1 \Rightarrow 2x=2 \Rightarrow x=1 \Rightarrow S_3=\{1\}\\ \\ S=S_1\cup S_2\cup S_3=\{0\}\cup (0,\ \ 1)\cup \{1\} =\[[0,\ \ 1][/tex]
