(2Sin3d - 3Cos3d)² + (2Cos3d + 3Sin3d)² =
= 4Sin²3d - 12Sin3dCos3d + 9Cos²3d + 4Cos²3d + 12Sin3dCos3d + 9Sin²3d = 13Sin²3d + 13Cos²3d = 13(Sin²3d + Cos²3d) = 13 * 1 = 13
(2Sin3d - 3Cos3d)² + (2Cos3d + 3Sin3d)² =
= 4Sin²3d - 12Sin3dCos3d + 9Cos²3d + 4Cos²3d + 12Sin3dCos3d + 9Sin²3d = 13Sin²3d + 13Cos²3d = 13(Sin²3d + Cos²3d) = 13 * 1 = 13