Question 1.89
59.
- Find the best eulerizations you can for the two accompanying graphs.
- Graph (a) can be thought of as having five rays and two circles, and graph (b) as having six rays and three circles. Draw a graph with four rays and four circles and find the best eulerization you can for this graph.
- Find a “formula” involving r and s for the smallest number of edges needed to eulerize a graph of this type having r rays and s circles.
59.
(a) Drawings can vary. Possible renderings include the following:
(b) The best eulerization for the four-circle, four-ray case adds two edges.
(c) Answers will vary.