The - 1125 ° is reduced to 2K π + α (0 ≤ α < 2 π, K ∈ z)

The - 1125 ° is reduced to 2K π + α (0 ≤ α < 2 π, K ∈ z)

 -1125°
= -1260° + 135°
= -7π + 3π/4