Which one of the following graphs is NOT planar?
why is g1 not planar? We can create planar structure of G1 also
??
@Pranav Madhani
You Number them first and then make planar(G1) you can not make the planar graph
A finite graph is planar if and only if it does not contain a subgraph that is a subdivision of the complete graph K5 or the complete bipartite graph K3,3 (utility graph). Source
G1 is exactly K3,3 but drawn in a different way. See this
We can form a planar graph for all except G1. Hence G1 is not planar graph.
if G1 is non-planar, then it shouldn't satisfy 3v-e>=6 this inequality right ? but it does 3*6-9>=6 --> 9>=6 (Satisfied)
It is necessary condition to be planar not sufficient.