International Journal of Mathematical Analysis Vol. 9, 2015, no. 32, 1579 - 1583 HIKARI Ltd, www.m-hikari.com http://dx.doi.org/10.12988/ijma.2015.53111 Clique Cover of the Join and the Corona of Graphs Rosalio G. Artes, Jr. Department of Mathematics and Statistics College of Science and Mathematics, MSU - Iligan Institute of Technology Andres Bonifacio Avenue, Tibanga, 9200 Iligan City, Philippines Frederick S. Gella Department of Mathematics, Institute of Arts and Sciences Far Eastern University, Manila, Philippines Copyright c  2015 Rosalio G. Artes, Jr. and Frederick S. Gella. This article is dis- tributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Let G be a graph. A clique of a graph G is a nonempty subset S of V (G) such that S induces a complete subgraph of G. A family F of cliques of G is a clique cover of G if for every v ∈ V (G) there exists S ∈F such that v ∈ S . The clique covering number of G is the minimum cardinality among the clique covers of G. In this paper, we give explicit forms of the clique covering of the join and the corona of graphs in terms of the clique covering numbers of graphs in consideration. Mathematics Subject Classification: 05C30 Keywords: clique, clique cover, clique covering number 1 Introduction Let G be a graph. A clique of a graph G is a nonempty subset S of V (G) such that S induces a complete subgraph of G. A family F of cliques of G is a clique cover of G if for every v ∈ V (G) there exists S ∈F such that v ∈ S . The clique covering number of G, denoted by cc(G), is given by cc(G) = min{|F| : F is a clique cover G}.