Сравните a) sin60° и tg(-45°) б) cos60° и cos60°×ctg30° в) sin30° и sin^2_30°

А)sin60° и tg(-45°)
sin60°=
tg(-45°)= tg135°=-1
sin60° > tg(-45°)
б) cos60° и cos60°×ctg30°
cos60°=
cos60°×ctg30°=*=
cos60° < cos60°×ctg30°
в) sin30° и sin²30°
sin30°=
sin²30°=sin30°*sin30°=*=
sin30° > sin²30°