Honors Discrete Chapter 5 Test Review Guide KEY TERMS. (8 Direct Definitions) 1) 2) 3) 4) 5) Loop Multiple Edges Isolated Vertex Vertex Set Edge Set 6) Adjacent 7) Degree of a Vertex 8) Path 9) Circuit 10) Connected Graph 11) Bridge 12) Euler Path 13) Euler Circuit SOME TYPES OF PROBLEMS TO EXPECT For the following graph: 1) Label any multiple edges, loops, isolated vertices, or bridges. A B C G 2) Find the vertex set, edge set, and degree of each vertex D E F For each prompt, DRAW a graph satisfying the characteristics: 1) Vertex Set = {A, B, C, D, E, F} and Edge Set = {AB, AC, AD, AF, BC, BE, CD, CE, DE, DF, FF} 2) A is adjacent to B and E. B is also adjacent to E. C is also adjacent to D and C. D is also adjacent to A and E. E is also adjacent to B. 3) The graph has 3 bridges and 4 vertices. 4) The graph has 4 odd vertices and 2 even vertices. 5) Disconnected in which each component has a bridge. 6) Has at least 2 multiple edges, 3 loops, 5 vertices, and 12 total edges. 7) Euler Path and odd vertices are not adjacent. GRAPH MODEL - draw a graphical representation of the following: What should be your edges and vertices? #1: Represent the enclosed neighborhood of homes and streets below. Shaded Regions are actual homes. #2: A river separates 5 islands from its north and south shore. Bridges now connect the islands to the shores. Isle #4 Isle #1 Isle #2 Isle #3 Isle #5 Does the Graph have an Euler Path, Euler Circuit, or Neither? If the graph has an Euler Path or Euler Circuit then find one. Find an Eulerization of the graphs: Find a Semi-Eulerization of the graph: E E S S Honors Discrete Chapter 5 Test Review Guide SOLUTIONS SOME TYPES OF PROBLEMS TO EXPECT For the following graph: Multiple Edges: BE, BC Loops: EE Bridges: AB, BD, EF, FG Isolated Vertex: None A B C G D Vertex set: A, B, C, D, E, F, G Edge set: AB, BC, BC, BC, BE, BE, BD, CE, EE, EF, FG Degree of each vertex: A=1 B=7 C=4 D=1 E=6 F=2 G=1 E F For each of the following prompts DRAW a graph satisfying the characteristics: 1) Vertex Set = {A, B, C, D, E, F}, 4) The graph has 4 odd vertices and 2 even Edge Set = {AB, AC, AD, AF, BC, BE, CD, vertices. CE, DE, DF, FF} B C A D 5) Disconnected in which each component has a bridge. F E 2) A is adjacent to B and E. B is also adjacent to E. C is also adjacent to D and C. D is also adjacent to A and E. E is also adjacent to B. C B 6) Has at least 2 multiple edges, 3 loops, 5 vertices, and 12 total edges. D A E 7) Euler Path and odd vertices are not adjacent. 3) The graph has 3 bridges and 4 vertices. Give a graphical representation of the following pictures: What should be edges and vertices? Land (Island and Shore) Streets = Edges = Vertices Intersections = Vertices Bridges = Edges Does the Graph have an Euler Path, Euler Circuit, or Neither? If the graph has an Euler Path or Euler Circuit then find one. 1 9 Neither. 4 vertices of degree 5 8 26 20 1 8 9 7 10 11 18 24 12 13 3 14 4 23 22 21 18 17 6 16 15 5 3 12 19 21 22 13 16 20 4 15 14 23 6 5 17 19 2 11 10 25 7 Euler Circuit. No vertices of odd degree 2 Euler Circuit. No vertices of odd degree Euler Path. 2 vertices of degree 3 Find an Eulerization of the graphs: Find a Semi-Eulerization of the graph: E E S S