Question

Упростить тригонометрические уравнения:

Answer 1

2)(1-sin^2(a)-2sina•cosa-cos^2(a))/(sina•cosa-cosa/sina)=
(-2sina•cosa)/(sin^2(a)cosa-cosa)sina=
(-2sin^2(a)•cosa/(cosa(sin^2(a)-1))=
=2sin^2(a)/cos^2(a)=2tg^2(a)