7 votes 7 votes The number of edges in a regular graph of degree: $d$ and $n$ vertices is: maximum of $n$ and $d$ $n +d$ $nd$ $nd/2$ Graph Theory isro2018 graph-theory graph-connectivity + – Arjun asked Apr 22, 2018 • edited Jan 24 by makhdoom ghaya Arjun 14.0k views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 10 votes 10 votes as every vertex has degree d,so sum of degrees is n*d. we know 2* number of edges = sum of degrees so,2*E = nd =>E=$\frac{nd}{2}$ Sambit Kumar answered Apr 22, 2018 • selected Apr 24, 2018 by ManojK Sambit Kumar comment Share Follow See all 0 reply Please log in or register to add a comment.
2 votes 2 votes Regular graph, a graph in which all vertices have same degree. example:- if n=3 and d=2 so there are 3*2/2 = 3 edges. if n=4 and d=2 so there are 4*2/2 = 4 edges. and so on. So option D is correct. Akshay Koli 4 answered Apr 22, 2018 Akshay Koli 4 comment Share Follow See all 0 reply Please log in or register to add a comment.
2 votes 2 votes Every complete graph with n vertices(Kn) is a regular graph of degree 'n-1' therefore no. of edges in Kn=n(n-1)/2 =n(d)/2 = ( n * d ) / 2 Shaik Masthan answered May 9, 2018 Shaik Masthan comment Share Follow See all 0 reply Please log in or register to add a comment.