Question

помогите с алгеброй срочно нужно

Answer 1

$frac{Sinalpha}{1+Cosalpha}+frac{1+Cosalpha }{Sinalpha}=frac{Sin^{2}alpha+(1+Cosalpha)(1+Cosalpha)}{Sinalpha(1+Cosalpha)}=frac{Sin^{2}alpha+1+2Cosalpha+Cos^{2}alpha}{Sinalpha(1+Cosalpha)}=frac{2+2Cosalpha}{Sinalpha(1+Cosalpha)}=frac{2(1+Cosalpha)}{Sinalpha(1+Cosalpha)}=frac{2}{Sinalpha }$

Второй способ :

$frac{Sinalpha }{1+Cosalpha}+frac{1+Cosalpha}{Sinalpha}=frac{2Sinfrac{alpha }{2}Cosfrac{alpha }{2}}{2Cos^{2}frac{alpha} {2}} +frac{2Cos^{2}frac{alpha}{2}}{2Sinfrac{alpha} {2} Cosfrac{alpha}{2}}=frac{Sinfrac{alpha }{2}}{Cosfrac{alpha }{2}}+frac{Cosfrac{alpha }{2} }{Sinfrac{alpha}{2} }=frac{Sin^{2}frac{alpha }{2}+Cos^{2}frac{alpha}{2}}{Sinfrac{alpha }{2}Cosfrac{alpha }{2}}=frac{1}{frac{1}{2}Sinalpha}=frac{2}{Sinalpha}$