Explicație pas cu pas:
a)
[tex]A = \{x \in \mathbb{N*} | {2}^{x} - 132 < 124 - 2\} \\ [/tex]
[tex]{2}^{x} - 132 < 124 - 2 \\ {2}^{x} < 254 \\ {2}^{7} = 128 < 254 < 256 = {2}^{8} \\ \implies 0 < x \leqslant 7[/tex]
[tex]\iff A = \{1; 2; 3; 4; 5; 6; 7\}[/tex]
[tex]B = \{x \in \mathbb{N} | x - 1 \in D_{15} \} \\ [/tex]
[tex](x - 1) \in \{1; 3; 5; 15\} \\ \implies x \in \{2; 4; 6; 16\}[/tex]
[tex]\iff B = \{2; 4; 6; 16\}[/tex]
b)
[tex]A \cup B = \{1; 2; 3; 4; 5; 6; 7; 16 \}[/tex]
[tex]A \cap B = \{2; 4; 6\}[/tex]
[tex]A {-} B = \{1; 3; 5; 7 \}[/tex]
[tex]B {-} A = \{16\}[/tex]
