hat
Pou egzanp, Z × = { − 1 , 1 } {\displaystyle \mathbb {Z} ^{\times }=\{-1,1\}} ak D × = { ± 2 a 5 b ∣ a , b ∈ Z } {\displaystyle \mathbb {D} ^{\times }=\{\pm 2^{a}5^{b}\mid a,b\in \mathbb {Z} \}} , tandike si A {\displaystyle A} se yon kò (kòm Q {\displaystyle \mathbb {Q} } , R {\displaystyle \mathbb {R} } oswa C {\displaystyle \mathbb {C} } ) A × = A ∗ {\displaystyle A^{\times }=A^{*}} .
fra
Par exemple, Z × = { − 1 , 1 } {\displaystyle \mathbb {Z} ^{\times }=\{-1,1\}} et D × = { ± 2 a 5 b ∣ a , b ∈ Z } {\displaystyle \mathbb {D} ^{\times }=\{\pm 2^{a}5^{b}\mid a,b\in \mathbb {Z} \}} , tandis que si A {\displaystyle A} est un corps (comme Q {\displaystyle \mathbb {Q} } , R {\displaystyle \mathbb {R} } ou C {\displaystyle \mathbb {C} } ), A × = A ∗ {\displaystyle A^{\times }=A^{*}} .