︱x-3︱+1/2 √(3-x) = y - 43 - x > = 0 ==> x < = 3︱x-3︱+1/2 √(3-x) = y - 4 ==> 3 - x + 1/2 √(3-x) = y - 4 ==> - x + 1/2 √(3-x) = y - 7 ==> x + y = 7 + 1/2 √(3-x) > = 7当x = 3 时,取最小值 7...