Ta có :
TH1 : \(x< -4\) ; ta có :
\(Q=\left[-\left(x-3\right)\right]+\left[-\left(x+4\right)\right]+x-5\)
\(=3-x-x-4+x-5\)
\(=-6-x\)
TH2 : \(-4\le x< 3\) , ta có :
\(Q=\left[-\left(x-3\right)\right]+\left(4-x\right)+x-5\)
\(=3-x+4-x+x-5\)
\(=2-x\)
TH3 : \(x\ge3\) , ta có :
\(Q=\left(x-3\right)+\left(4+x\right)+x-5\)
\(=x-3+4+x+x-5\)
\(=3x-4\)
Q= \(\left|x-3\right|\) + \(\left|4+x\right|\) + x - 5
= x - 3 + 4 + x + x -5
= 3x - 4