0\\tg\left(-\frac{13\pi}6\right)=-tg(390^o)<0\\\\4.\;\cos765^o=\cos\frac{17\pi}4=\cos(2\pi+\frac\pi4)=\cos\frac\pi4=\frac1{\sqrt2}\\ctg\frac{19\pi}4=ctg\left(4\pi+\frac{3\pi}4\right)=ctg\frac{3\pi}4=-1" alt="1.\\\frac{7\pi}6=\frac{7\cdot180}{6}=7\cdot30=210^o\\\frac{11\pi}5=\frac{11\cdot180}5=11\cdot36=396^o\\\\2.\\330^o=\frac{330\pi}{180}=\frac{11\pi}6\\\\120^o=\frac{120\pi}{180}=\frac{2\pi}3\\\\3.\;160^o\;-\;II\;4ETB.,\sin160^o>0\\tg\left(-\frac{13\pi}6\right)=-tg(390^o)<0\\\\4.\;\cos765^o=\cos\frac{17\pi}4=\cos(2\pi+\frac\pi4)=\cos\frac\pi4=\frac1{\sqrt2}\\ctg\frac{19\pi}4=ctg\left(4\pi+\frac{3\pi}4\right)=ctg\frac{3\pi}4=-1" align="absmiddle" class="latex-formula">
