Answer:
Step-by-step explanation:
[tex]sin({\alpha\over{2}})=\pm\sqrt{{1-cos(\alpha)\over{2}}}\Rightarrow sin({30\over{2}})=+\sqrt{{1-{\sqrt{3}\over{2}}\over{2}}}={\sqrt{{2-\sqrt{3}}}\over{2}}[/tex]
[tex]cos({\alpha\over{2}})=\pm\sqrt{{1+cos(\alpha)}\over{2}}=+\sqrt{{1+{\sqrt{3}\over{2}}\over{2}}}={\sqrt{{2+\sqrt{3}}}\over{2}}[/tex]
substituting we get:
[tex]tg(15)=\sqrt{{2-\sqrt{3}}\over{2+\sqrt{3}}}[/tex]
