The hyperbolic or Gudermannian amplitude of the quantity x is ta n (sinh x).
The cartesian equation referred to the axis and directrix is y=c cosh (x/c) or y = Zc(e x / c +e x / c); other forms are s = c sinh (x/c) and y 2 =c 2 -1-s 2, being the arc measured from the vertex; the intrinsic equation is s = c tan The radius of curvature and normal are each equal to c sec t '.
If A, B have opposite signs the form is au = sinh mO, (24) this has an asymptote parallel to 0=0, but the path near the origin has the same general form as in the case of (23).
The Lao Loum women wear the traditional sinh - the wraparound sarong.