`3, //3/4-1/2x//+1/3=5/6`
`⇔//3/4-1/2x//=5/6-1/3`
`⇔//3/4-1/2x//=1/2`
`TH1`
`3/4-1/2x=1/2`
`⇔1/2x=3/4-1/2`
`⇔1/2x=1/4`
`⇔x=1/2`
`TH2`
`3/4-1/2x=-1/2`
`⇔1/2x=3/4-(-1/2)`
`⇔1/2x=5/4`
`⇔x=3/4`
Vậy `x∈{1/2;3/4}`
`4, //x+3/4//-1/2=0`
`⇔//x+3/4//=1/2`
`TH1`
`x+3/4=1/2`
`⇔x=1/2-3/4`
`⇔x=-1/4`
`TH2`
`x+3/4=-1/2`
`⇔x=-1/2-3/4
`⇔x=-5/4`
Vậy `x∈{-1/4;-5/4}
`5, //x-2/5//=1/4`
`TH1`
`x-2/5=1/4`
`⇔x=1/4+2/5`
`⇔x=13/20`
`TH2`
`x-2/5=-1/4`
`⇔x=-1/4+2/5`
`⇔x=3/20`
Vậy `x∈{13/20;3/20}`
`8, //x+2/5// -1/3=1/3`
`⇔/x+2/5/ =2/3`
`TH1`
`x+2/5=2/3`
`⇔x=2/3-2/5`
`⇔x=4/15`
`TH2`
`x+2/5=-2/3`
`⇔x=-2/3-2/5`
`⇔x=-16/15`
Vậy `x∈{4/16;-16/15}`
`9,`
`7,5-3//5-2x//=-4,5`
`⇔3//5-2x//=7,5-(-4,5)`
`⇔3//5-2x//=12`
`⇔//5-2x//=4`
`⇔2x=1`
`⇔x=1/2`
Vậy `x=1/2`
`10, //x-3,5//+//x-1,3//=0`
`TH1`
`x-3,5=0`
`⇔x=3,5`
`TH2`
`x-1,3=0`
`⇔x=1,3`
Vậy `x∈{3,5;1,3}`
