D⊂R\mathrm{D} \subset \mathrm{R}D⊂R
D={x∣x∈Z}D=\{x \mid x \in Z\}D={x∣x∈Z}
D={x∣x∈N}D=\{x \mid x \in N\}D={x∣x∈N}
D={x∣x≥0}D=\{x \mid x \geq 0\}D={x∣x≥0}
D={x∣x>0}D=\{x \mid x>0\}D={x∣x>0}