∵|X+1|+|X-2|Y-2|+|Y+1|≥|(Y+1)-(Y-2)|=3|Z-3|+|Z+1|≥|(Z+1)-(Z-3)|=4∴(|X+1|+|X-2|)(|Y-2|+|Y+1|)(|Z-3|+|Z-1|)≥3*3*4=36∴-1≤X≤2-1≤Y≤2-1≤Z≤3∴-6≤X+2Y+3Z≤15X+2Y+3Z的最小是-6