> 0 and f is superlinear, i.e., f(u)fu is monotone increasing. The goal is to : J, such that there is at most one positive solution of the differential 8uf 8a satisfies the [q(r)f'(u)]w w'(O)

ABSTRACT

As an example, we choose z(r) = (b-r)u'(r), which is negative in (O,b). For this choice MAPLE gives

expression L[z] for any choice of z. Here is an example, where we substitute z(r) r2u' + bu; u1 and u2 stand for u' and u11 , respectively.