abstract: In this talk, first, I will tell about Wigner Semicircle Law and some results on asymptotic expansions. After that, I’ll introduce Kopelevitch’s theorem on convergent asymptotic expansion for Gaussian Unitary Ensemble. In the end, I’ll tell about generalizations of this results to all Gaussian Ensembles. Also, I’ll include some intermediate results: differential equations on the densities and their moment generating functions for all Gaussian Ensembles and explicit formulas for Kopelevitch’s theorem.