Suppose that A and B are two positive-definite matrices,then,the limit of (Ap/2BpAp/2)1/p as p tends to 0 can be obtained by the well known Lie-Trotter formula.In this article,we generalize the usual product of matrices to the Hadamard product denoted as * which is commutative,and obtain the explicit formula of the limit (Ap * Bp)1/p as p tends to 0.Furthermore,the existence of the limit of (Ap * Bp)1/p as p tends to +∞ is proved.