Uzasadnij tożsamość:
α - alfa
a) tg^2 α-sin^2 α=tg^2 α*sin^2 α
b) cos α/tg α+sin α=1/sin α
c) (cos α/sin α-1)+tg α= -1/cos α
d) 1/1+tg^2 α=(1-sin α)(1+sin α)
e) 2/cos^2 α-(tg α+1/tg α)^2=tg^2 α-1/tg^2 α
f) 1-2sin^2 α*cos^2 α=sin^4 α+cos^4 α​