Bài 1:
a,
C1: A={5; 6; 7}
C2: A={x ∈ N| 4<x≤7}
b,
C1: B={1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12}
C2: B={x ∈ N*| 0<x≤12}
c,
C1: M={11; 12; 13; 14; 15; 16; 17; 18; 19; 20}
C2: M={x ∈ N|11≤x≤20}
Bài 2:
a, A={11; 12; 13; 14; 15}
b, B={10; 11; 12; 13; 14; 15; 16; 17; 18; 19; 20}
c, C={6; 7; 8; 9; 10}
d, F={1; 2;3 ;4; 5; 6; 7; 8; 9}
e, G={1; 2; 3; 4}
Bài 3:
a, A={9; 7; 5; 4; 2}
b, B={2; 9; 6; 3; 5}
c, C={6; 0}
@Nhi6aphtn
20h33' p.m
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