Решите уравнения:
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1. cos(π/4 + x) = 0
π/4 + x = π/2 + πn, n ∈ Z
x = π/2 - π/4 + πn, n ∈ Z
x = π/4 + πn, n ∈ Z.
Ответ: x = π/4 + πn, n ∈ Z.

2. sin(4x - π/4) = 0
4x - π/4 = πn, n ∈ Z
4x = πn + π/4, n ∈ Z
x = π/16 + πn/4, n ∈ Z.
Ответ: х = π/16 + πn/4, n ∈ Z.