\frac{sin(30+ \alpha)-cos(60+ \alpha )}{sin(30+ \alpha) +cos(60+ \alpha)} = \frac{sin30cos \alpha +cos30sin \alpha-(cos60cos \alpha-sin60sin \alpha )}{sin30cos \alpha +cos30sin \alpha+cos60cos \alpha-sin60sin \alpha } ==\frac{ \frac{1}{2} cos \alpha+ \frac{ \sqrt{3}}{2} sin \alpha- \frac{1}{2} cos \alpha+\frac{ \sqrt{3}}{2} sin \alpha}{\frac{1}{2} cos \alpha+\frac{ \sqrt{3}}{2} sin \alpha +\frac{1}{2} cos \alpha-\frac{ \sqrt{3}}{2} sin \alpha}==\frac{ \sqrt{3}sin \alpha }{cos \alpha } = \sqrt{3} tg \alpha