Can somebody tell me if it possible to run a non-linear multiple regression in R, without specifying the coefficients exactly, as they are in the examples? For instance, set a b vector and then form a non-linear regression problem, e.g. y~exp(x %*% b).

Can somebody tell me if it possible to run a non-linear multiple regression in R, without specifying the coefficients exactly, as they are in the examples? For instance, set a b vector and then form a non-linear regression problem, e.g. y~exp(x %*% b).