A) arcsin (cos 22pi/5) b) sin (arccos (-2/5)

А)

ArcSin (Cos (22 п/5)) = ArcSin (Cos (2 п + 2 п + 2 п/5)) = ArcSin (Cos (2 п/5)) = п/2 - ArcCos (Cos (2 п/5)) = п/2 - 2 п/5 = п/10

Б) Sin (Arccos (-2/5)) = √ (1 - Cos² (Arccos (-2/5))) = √ (1 - (2/5) ²) = (√21) / 5