The set of points in a plane between two parallel straight lines in this plane. The coordinates $ x , y $
of a point in a strip satisfy inequalities $ C _ {1} < Ax + By < C _ {2} $,
where $ A $,
$ B $,
$ C _ {1} $,
$ C _ {2} $
are certain constants with $ A $
and $ B $
not both equal to zero. The function $ w = e ^ {z} $
maps the strip $ 0 < y < \pi $
in the complex plane $ ( z = x + iy ) $
conformally onto the upper half-plane of the complex $ w $-
plane.
[a1] | R.V. Churchill, J.W. Brown, R.F. Verhey, "Complex variables and applications" , McGraw-Hill (1974) |