Răspuns:
1. AUB={1, 4, 10, 8, 20} -reuniune
A∩B={4, 10} -intersectie
A\B={1, 20} - ce e in A si nu e in B
B\A = {8} - ce e in B si nu e in A
2.
2x-1<=7
2x<=8
x<=4
x∈N
=> A={0, 1 , 2 3, 4}
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3x+6>12
3x>6
x>2
x∈N
B={3,4, ...∞}
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C={3, 6} - singurele numere divizibile cu 3 si mai mici strict decat 9
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AUBUC = N (multimea nr naturale)
A∩B∩C={3}
AUC = {0,1, 2, 3, 4, 6}
B\(AUC)={5, 7, 8, ...∞}
3. D4 = {1, 2, 4}
D4={1}
D4={2}
D4={4}
D4={1, 2}
D4={2, 4}
D4={1, 4}
4.
a)M3 ∩ D24={3, 6, 12, 24}
b)D24\M3={1, 2, 4, 8}
5. Aici nu vad care este forma.... aba7 si mai ce?
6.
4800/2=2400/2=1200/2=600/2=300/2=150/2=75/3=25/5=5/5=1
4800 = [tex]2^{6}[/tex]x3x[tex]5^{2}[/tex]
4851/3 =1617/3 =539/7=77/7=11/11=1
4851=[tex]7^{2}[/tex]x[tex]3^{2}[/tex]x11
