Cos(2x-1)=-v2/2 Tgп/x=7 Sin2x=П/4 Ctgx=tgп/3

1) cos(2x - 1) = - √2/2;

2x - 1 = arccos(-√2/2) +- 2 * π * n, где n - натуральное число;

2x = - π/4 + 1 +- 2 * π * n;

x = - π/8 + 1/2 +- π * n.

2) tg(π/x) = 7;

π/x = arctg(7) +- π * n;

1/x = arctg(7)/π +- n;

x = 1 / ( arctg(7)/π +- n).

3) sin(2x) = π/4;

2x = arcsin(π/4) +- 2 * π * n;

x = √2 / 4 +- π * n.

4) Так как  tg(π/3) = √3, получим уравнение:

ctg(x) = √3;

x = arcctg(√3) +-  π * n;

x = π/6 +-  π * n.