Đáp án:
Nếu `x>=2/5`
`=>|x-2/5|=x-2/5,|x+1/3|=x+1/3`
`=>|x-2/5|+|x+1/3|-2(x-1/2)`
`=x-2/5+x+1/3-2x+1`
`=3/5+1/3=14/15`
Nếu `x<=-1/3`
`=>|x-2/5|=2/5-x,|x+1/3|=-x-1/3`
`=>|x-2/5|+|x+1/3|-2(x-1/2)`
`=2/5-x-x-1/3-2x+1`
`=-4x+2/5+2/3`
`=-4x+16/15.`
Nếu `-1/3<=x<=2/5`
`=>|x-2/5|=2/5-x,|x+1/3|=x+1/3`
`=>|x-2/5|+|x+1/3|-2(x-1/2)`
`=2/5-x+x+1/3-2(x-1/2)`
`=2/5+1/3-2x+1`
`=-2x+2/5+4/3`
`=-2x+26/15.`