We prove a theorem on the uniqueness of positive radial solutions to a Diri
chlet problem of the n-Laplacian in a finite ball of R-n. Our proofs use on
ly elementary analysis based on an identity due to Erbe and Tang. The resul
t can be applied to a large class of nonlinearities, including some polynom
ials and functions with exponential growth; in particular, the one recently
studied by Adimurthi.