Abstract:

We obtained the generalized characteristic polynomial of two classes of composite graphs by using block matrix, the coronal of matrix and Schur complement, and then gave the adjacency, Laplacian, signless Laplacian and normalized Laplacian characteristic polynomial of these two classes of compo
site graphs, respectively. We extended the scope of generalized cospectral graphs by proving some generalized cospectral graphs.

Key words: generalized characteristic polynomial, graph spectrum, generalized cospectral graph