Question

Ex 1 va rog frumos dau coroana

Answer 1

$D_{2} = \left \{ \pm1,\pm2 \right \}$

$D_{3} = \left \{ \pm1,\pm3\right \}$

$D_{14} = \left \{ \pm1,\pm2,\pm7,\pm14\right \}$

$D_{30} = \left \{ \pm1,\pm2,\pm3,\pm5,\pm6,\pm10,\pm15,\pm30\right \}$

$D_{47} = \left \{ \pm1,\pm47\right \}$