1)cos=1/4⇒sin; tg-? 2)sin=0.8⇒cos; tg-?

1) sin^2=1-1/16 sin^2=15/16 sin=sqrt(15)/4 tg=sqrt(15)/4/1/4 2)cos^2=0.36 cos=0.6 tg=0.8/0.6