Question

ПОМОГИТЕ ДОПИСАТЬ ФОРМУЛЫ

Answer 1

$tgalphacdot ctgalpha=1\sin^2alpha=1-cos^2alpha\cos^2alpha-1=-sin^2alpha\1-sin^2alpha=cos^2alpha\1-ctg^2alpha=?\sin^2alpha-1=-cos^2alpha\tgalpha=frac{sinalpha}{cosalpha}$