Abstract
The lower bounds of mu-values for a family of square real and complex valued matrices are computed analytically. The proposed methodology consists of factorizing an admissible perturbation from a set of block diagonal matrices into a block diagonal matrix. The computation of the lower bounds of mu-values is then carried out by computing the spectral radius and numerical radius for matrix under consideration. The lower bounds of mu-value provide the conditions which guarantee the instability analysis of the linear feedback system. (C) 2020 The Authors. Published by IASE.