Răspuns :
A={x € R | |x+1|≤4}
x+1≤4
x≤4-1
x≤3
x+1≥0
x+1-1≥0-1
x≥-1
-(x+1)≤4
x+1≥-4
x≥-4-1
x≥-5
x+1<0
x+1-1<0-1
x<-1
x € [-1,3]
x € [-5,-1)
=>x € [-5,3]
x+1≤4
x≤4-1
x≤3
x+1≥0
x+1-1≥0-1
x≥-1
-(x+1)≤4
x+1≥-4
x≥-4-1
x≥-5
x+1<0
x+1-1<0-1
x<-1
x € [-1,3]
x € [-5,-1)
=>x € [-5,3]