2x-7<=3 ( scriu < pt. mai mic sau egal, intelegi tu. ;) )
2x<3+7
2x<10
x<10:2
x<5
x={1, 2, 3, 4, 5}
2x+1/9<1
2x+1<1*9
2x+1<9
2x<9-1
2x<8
x<8:2
x<4
x={1,2,3,4)
A={1, 2, 3, 4,5}
B={1,2,3, 4}
A U B = {1, 2, 3, 4, 5}
A inetsectat B = {1, 2, 3, 4}
A/B={5}
B/A={ Multimea vida (un o taiat)}
