- $ D = \\\left( {\\\frac{1}{2};\\\,\\\, + \\\infty } \\\right)$.
- $ D = \\\mathbb{R}$.
- $ D = \\\left[ {\\\frac{1}{2};\\\,\\\, + \\\,\\\infty } \\\right)$.
- $ D = \\\,\\\,\\\mathbb{R}\\\backslash \\\left\\\{ {\\\frac{1}{2}} \\\right\\\}$.