Ctg (3n/2-2x) - корень 3=0 2cos2x=-1 15cos (n/2-5x) = 0 2cos (2x-3) + 1=0 cos (n/2-2x/3) = sin n/3

1. ctg (3π/2 - 2x) - √3 = 0;

ctg (3π/2 - 2x) = √3;

3π/2 - 2x = arcctg (√3) + - π * n, где n натуральное число;

3π/2 - 2x = π/6 + - π * n;

-2x = - 4π/3 + - π * n;

x = 2π/3 + - π/2 * n.

2. cos (2x) = - 1;

2x = arccos (-1) + - 2 * π * n;

2x = π + - 2 * π * n;

x = π/2 + - π * n.

3. 15cos (π/2 - 5x) = 0;

cos (π/2 - 5x) = 0;

π/2 - 5x = arccos (0) + - 2 * π * n;

π/2 - 5x = 0 + - 2 * π * n;

-5x = - π/2 + - 2 * π * n;

x = π/10 + - 1/5 * π * n;

4) 2cos (2x - 3) + 1 = 0;

cos (2x - 3) = - 1/2;

2x = 2π/3 + 3 + - 2 * π * n;

x = π/3 + 3 + - π * n.