Question

A={x€N*/3x-1< cu liniuta 2x-1}
B={x€A/x>8}
C={x€N/3x-6> cu liniuta2x+1}
D={x€C/2x BuD CnA
Va rog repede va dau coroana

Answer 1

A
3x ≤ 2x+1
3x-2x ≤ 1
x ≤ 1
x € {1}, x€N*
A= {1}

B
x > 8
x € {9, 10, 11, 12, 13, 14, ..........}
B = {9, 10, 11, 12, 13, 14, 15, .......}

C
3x-6 ≥ 2x-1 /+1
3x-5 ≥ 2x
3x-2x ≥ 5
x ≥ 5
C= {5, 6, 7, 8, ............}

D= 2•x, x€C
D= {10, 12, 14, 16, ..........}

B U D = {9, 10, 11, 12, 13, 14, 15, 16, 17, ....}
C Π A = ∅

Asta e tot... Succes!