Помогите решить 15.9, пожалуйста:3
Решение 1) arccosx -1 ≤ x ≤ 1 2) arccos2x -1 ≤ 2x ≤ 1 - 1/2 ≤ x ≤ 1/2 3) arcco(x - 1) -1 ≤ x - 1 ≤ 1 - 1 + 1 ≤ x ≤ 1 + 1 0 ≤ x ≤ 2 arccos(3 - 2x) -1 ≤ 3 - 2x ≤ 1 - 1 - 3 ≤ - 2x ≤ 1 - 3 - 4 ≤ - 2x ≤ - 2 1 ≤ x ≤ 2