3. Sin2(ankyan astichan@)+cos2(ankyan
astichan@)=1
Ctg2(ankyan astichan@)=cos(ankyan
astichan@)/sin(ankyan astichan@)
Tg(ankyan astichan@)=sin(ankyan
astichan@)/cos(ankyan astichan@)
tg(ankyan astichan@)*ctg(ankyan astichan@)=1