Vector3D v = new Vector3D(1, 0, 0); Vector3D p = Vector3D.CalculatePerpendicularVector(v); // p is now (0, 1, 0)In this example, we create a Vector3D object with the values (1, 0, 0). We then call the CalculatePerpendicularVector method on this vector, which returns a new vector that is perpendicular to the original vector. The resultant vector p is (0, 1, 0). Another example of using this method is in 3D graphics and computer vision applications where it is used to find normals to surfaces. The Vector3D class is part of the System.Windows.Media.Media3D namespace, which is part of the PresentationCore.dll assembly in the .NET Framework.