Question

упростите выражения
(и мою жизнь)​

Answer 1

$1)frac{Sin2alpha}{Sinalpha}=frac{2Sinalpha Cosalpha}{Sinalpha}=2Cosalpha$

$2)frac{Sin2alpha}{Cos^{2}alpha-Sin^{2}alpha}=frac{Sin2alpha}{Cos2alpha}=tg2alpha$

$3)Cos2alpha+Sin^{2} alpha=Cos^{2}alpha-Sin^{2}alpha+Sin^{2}alpha=Cos^{2}alpha$

$4)frac{Sin50^{0}}{2Cos25^{0}}=frac{2Sin25^{0}Cos25^{0}}{2Cos25^{0}}=Sin25^{0}$

$5)frac{Cos2alpha}{Cosalpha-Sinalpha}=frac{Cos^{2}alpha-Sin^{2}alpha}{Cosalpha-Sinalpha}=frac{(Cosalpha-Sinalpha)(Cosalpha+Sinalpha)}{Cosalpha-Sinalpha}=Cosalpha+Sinalpha$

$6)1-2Sin^{2}frac{alpha}{4} = Cos(2*frac{alpha}{4})=Cosfrac{alpha}{2}$