不知道你说的这个式子是(3x+4)/5 还是(3x/5)+4 ,都求一下吧
要是(3x+4)/5
-1 <= (3x+4)/5 <= 2
-5 <= 3x+4 <= 10
-9 <= 3x <= 6
-3 <= x <= 2
x的整数解为:-3,-2,-1,0,1,2,其和为-3
要是(3x/5)+4
-1 <= (3x/5)+4 <= 2
-5 <= 3x/5 <= -2
-25 <= 3x <= -10
-25/3 <= x <= -10/3
x的整数解为:-8,-7,-6,-5,-4,其和为-30
1<(3x+4)/5<=2
-5<3x+4<=10
-9<3x<=6
-3
∴和为0