On the change of distance energy of complete bipartite graph due to edge deletion (Q1983412)

Summary: The distance energy of a graph is defined as the sum of absolute values of distance eigenvalues of the graph. The distance energy of a graph plays an important role in many fields. By constructing a new polynomial, we transform a problem on the sum of the absolute values of the roots of a quadratic polynomial into a problem on the largest root of a cubic polynomial. Hence, we give a new and shorter proof on the change of distance energy of a complete bipartite graph due to edge deletion, which was given by \textit{A. Varghese} et al. [Linear Algebra Appl. 553, 211--222 (2018; Zbl 1391.05179)].