Question

Срочно! Пожалуйста помогите

Answer 1

Используем формулы:

$cos2alpha=cos^2alpha-sin^2alpha\\sin2alpha=2sinalpha*cosalpha$

Решение.

$frac{1-cos2alpha+sin2alpha}{1+cos2alpha+sin2alpha}=tgalpha\\frac{1-(cos^2alpha-sin^2alpha)+2sinalpha*cosalpha}{1+(cos^2alpha-sin^2alpha)+2sinalpha*cosalpha}=tgalpha\\frac{(1-cos^2alpha)+sin^2alpha+2sinalpha*cosalpha)}{(1-sin^2alpha)+cos^2alpha +2sinalpha*cosalpha}=tgalpha\\frac{sin^2alpha+sin^2alpha+2sinalpha*cosalpha)}{cos^2alpha+cos^2alpha +2sinalpha*cosalpha}=tgalpha$

$frac{2sin^2alpha+2sinalpha*cosalpha)}{2cos^2alpha+2sinalpha*cosalpha}=tgalpha\\frac{2sinalpha*(sinalpha +cosalpha)}{2cosalpha*(cos  alpha +sinalpha)}=tgalpha\\frac{sinalpha}{cosalpha}=tgalpha\\tgalpha=tgalpha$