[tex]\cos 30=\frac{\sqrt{3}}{2}[/tex]
[tex]\sin 30 = \frac{1}{2}[/tex]
[tex]\tan 30=\frac{1}{\sqrt{3}}[/tex]
Now we insert that into the equation:
[tex]\dfrac{\frac{\sqrt{3}}{2}}{1+\frac{1}{2}} = \frac{1}{\sqrt{3}}[/tex]
[tex]\dfrac{\frac{\sqrt{3}}{2}}{\frac{3}{2}} = \frac{1}{\sqrt{3}}[/tex]
[tex]\frac{\sqrt{3}}{3} = \frac{1}{\sqrt{3}}[/tex]
[tex]\frac{\sqrt{3}}{3} = \frac{1}{\sqrt{3}}\cdot \frac{\sqrt{3}}{\sqrt{3}}\\[/tex]
[tex]\frac{\sqrt{3}}{3} = \frac{\sqrt{3}}{\sqrt{3}\cdot \sqrt{3}}\\[/tex]
[tex]\frac{\sqrt{3}}{3} = \frac{\sqrt{3}}{3}[/tex]