GATE CSE
First time here? Checkout the FAQ!
x
+2 votes
471 views

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 (76k points)   | 471 views

2 Answers

+2 votes
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 (24.4k points)  
+2 votes
B.chromatic number is the number to color a graph with minimum number of colors. so ans is K
answered by Loyal (3.1k 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.


Top Users Mar 2017
  1. rude

    5246 Points

  2. sh!va

    3054 Points

  3. Rahul Jain25

    2920 Points

  4. Kapil

    2732 Points

  5. Debashish Deka

    2602 Points

  6. 2018

    1574 Points

  7. Bikram

    1444 Points

  8. Vignesh Sekar

    1440 Points

  9. Akriti sood

    1424 Points

  10. Sanjay Sharma

    1128 Points

Monthly Topper: Rs. 500 gift card

21,556 questions
26,907 answers
61,268 comments
23,278 users