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+3 votes

If a graph requires $k$ different colours for its proper colouring, then the chromatic number of the graph is

  1. 1
  2. k
  3. k-1
  4. k/2
asked in Graph Theory by Veteran (78.2k points)   | 873 views

2 Answers

+6 votes
Best answer
The chromatic number of a graph is the smallest number of colors needed to color the vertices so that no two adjacent vertices share the same color.

Ans- Chromatic number = k
answered by Veteran (25k points)  
selected by
+2 votes
B.chromatic number is the number to color a graph with minimum number of colors. so ans is K
answered by Loyal (3.3k points)  
chromatic number is  n only for complete graph.Here in the question it is not mentioned whether it is complete or not
yes, in question it is not given that it is complete or not. But here it is  not necessary.

If a graph  colored with n color then chromatic number should be n.Right?Read Question Properly.

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