Hi all.

I am having trouble with the following problem:

Given the PDE: ,

where f is a differentiable function,

and the IVP: , h another function.

(a) Show that u satisfies the implicit equation: .

(b) Show that the solution becomes singular at some positive time t, unless ) is a non-decreasing function of s.

I can derive the solution in (a), but (b) has me totally perplexed. Thanks in advance!