Răspuns:
A={3;4;7}
B={-9;3;4;5;69;18}
Explicație pas cu pas:
2n-7/5n+14|×2. =>2n-7/10n+28
2n-7/2n-7|×5=>2n-7/10n-35
2n-7/10n+28-10n-35
2n-7/-7 => 2n-7€D7={-1;+1;-7;+7}
2n-7=-1. 2n-7=1
2n=6. 2n=8
n=3. n=4
2n-7=-7. 2n-7=7
2n=0. 2n=14
n=0. 2n=7
2n-9/5n+9|×2 => 2n-9/10n+18
2n-9/2n-9|×5 =>2n-9/10n-45
2n-9/-27=>2n-9€D27={+-1;+-3;+-9;+-27}
2n-9=1. 2n-9=-1. 2n-9=3. 2n-9=-3
2n=10. 2n=8. 2n=12. 2n=6
n=5. n=4. n=6. n=3
2n-9=9 2n-9=-9. 2n-9=27
2n=18. 2n=0. 2n=36
n=9. n=0. n=18
2n-9=-27
2n=-18
n=-9
