Răspuns:
8.
A = { x I x∈N, x≤12}⇒A={0,1,2,3,4,5,6,7,8,9,10,11,12}
B = { x I x∈N, x numar par, x ≤ 16} B={0,2,4,6,8,10,12,14,16}
C = { x I x∈N, x numar impar, x ≤ 15} C ={1,3,5,7,9,11,13,15}
D = { x I x = 3n ≤ 15, n∈N}
E = { x I x = n² ≤ 36 n∈N}
9.
a) 5x + 4 =19
5x =19 -4
5x = 15
x =3
A={3} multime finita
b)
x - 7 < 3
x < 7+3
x< 10∈N
B∈ {1,2,3,4,5,6,7,8,9} este multime finita
C este multime infinita
C ∈ {0 , 3 , 6, 9, 12..................}
D este multime infinita
D ∈ { 1 , 4, 7 ,10 .....}
Explicație pas cu pas:
