а) Sin(697°) = Sin(697° - 360°) = Sin(337°) = Sin(360° - 337°) = Sin(23°) ≈ 0.3907
б) ctg(13π/9) = 1/tan(13π/9) = 1/tan(13π/9 - 2π) = 1/tan(5π/9) ≈ 1/1.3764 ≈ 0.7265
а) Sin(697°) = Sin(697° - 360°) = Sin(337°) = Sin(360° - 337°) = Sin(23°) ≈ 0.3907
б) ctg(13π/9) = 1/tan(13π/9) = 1/tan(13π/9 - 2π) = 1/tan(5π/9) ≈ 1/1.3764 ≈ 0.7265