ТРИГОНМИЕТРИЧЕСКИЕ НЕРАВЕНСТВА. 10 КЛАСС Объясните пожалуйста

[latex]12)\; \; \; \; \; tgx\ \textgreater \ \sqrt3\\\\\frac{\pi}{3}+\pi n\ \textless \ x\ \textless \ \frac{\pi}{2}+\pi n,\; n\in Z\\\\ili\quad 60^\circ+180^\circ n\ \textless \ x\ \textless \ 90^\circ+180^\circ n\; ,\; n\in Z\\\\1\, radian\approx 57,3^\circ \; \; \Rightarrow\; \; 1,1radian\approx 1,1\cdot 57,3^\circ =63,03^\circ \\\\60^\circ\ \textless \ 63,03^\circ \ \textless \ 90^\circ \\\\Otvet:\; \; 1,1\; .[/latex] [latex]13)\; \; \; \; cosx\ \textgreater \ \frac{1}{2}\\\\-\frac{\pi }{3}+2\pi n\ \textless \ x\ \textless \ \frac{\pi}{3}+2\pi n,\; n\in Z\\\\\frac{\pi}{3}\approx \frac{3,14}{3}=1,05\\\\-1,05\ \textless \ 0,5\ \textless \ 1,05\\\\Otvet:\; \; 0,5\; .[/latex]