x apartine N
a)(3x+2)/(2x+3)=4/3
Faci inmultirea mezilor si inmultirea extremilor:
3(3x+2)=4(2x+3)
9x+6=8x+12
9x-8x=12-6
x=6. care apartine lui N
b)1/(2x+4)<2/(6x+2)
Idem a):
6x+2<2(2x+4)
6x+2<4x+8
6x-4x<8-2
2x<6 | :2
x<3
x apartine (-infinit, 3) intersectat cu N={0,1,2}
