[tex]\bf a)\; D_{ -14 } \; \cap \; \mathbb{N} = \Big\{ 1;2;7;14 \Big\}[/tex]
[tex]\bf D_{-14} \; \cap \; \mathbb{Z} = \Big\{ -14;-7;-2;-1;1;2;7;14\Big\}[/tex]
[tex]\bf \;[/tex]
[tex]\bf b)\; D_{-15} \; \cap \; \mathbb{N} = \Big\{ 1;3;5;15 \Big\}[/tex]
[tex]\bf D_{-15} \; \cap \; \mathbb{Z} = \Big\{ \pm 1 ; \pm 3 ; \pm 5 ; \pm 15\Big\}[/tex]
[tex]\bf \;[/tex]
[tex]\bf c)\; D_{-18} \; \cap \; \mathbb{N} = \Big\{ 1;2;3;6;9;18 \Big\}[/tex]
[tex]\bf D_{-18} \; \cap \; \mathbb{Z} = \Big\{ \pm1 ;\pm2; \pm 3 ; \pm 6; \pm9; \pm18 \Big\}[/tex]
[tex]\bf \;[/tex]
[tex]\bf d) \; D_{24} \; \cap \; \mathbb{N} = \Big\{ 1;2;3;4;6;8;12;24 \Big\}[/tex]
[tex]\bf D_{24} \; \cap \; \mathbb{Z} = \Big\{ \pm1;\pm2;\pm3;\pm4;\pm6;\pm8;\pm12;\pm24 \Big\}[/tex]
[tex]\bf \;[/tex]
[tex]\bf e)\; D_{-37} \; \cap \; \mathbb{N} = \Big\{1;37 \Big\}[/tex]
[tex]\bf D_{-37} \; \cap \; \mathbb{Z} = \Big\{ \pm1;\pm37\Big\}[/tex]
[tex]\bf \;[/tex]
[tex]\bf f)\; D_{-21} \; \cap \; \mathbb{N} = \Big\{ 1;3;7;21 \Big\}[/tex]
[tex]\bf D_{-21} \; \cap \; \mathbb{Z} = \Big\{ \pm1;\pm3;\pm7;\pm21 \Big\}[/tex]
[tex]\bf \;[/tex]
[tex]\bf g)\;h)\; D_{-1 \; sau \; 1 } \; \cap \; \mathbb{N} = \Big\{ 1 \Big\}[/tex]
[tex]\bf D_{-1 \; sau \; 1 } \; \cap \; \mathbb{Z} = \Big\{ 1;-1 \Big\}[/tex]
[tex]\bf \;[/tex]
#copaceibrainly
