Sublinear singular elliptic problems with two parameters. (Q1419814)

Let \(\Omega\) be a smooth bounded domain in \(\mathbb R^N\) \((N\geq 2)\). The authors study the existence or nonexistence of solutions to the following boundary value problem \[ \begin{cases} -\Delta u+ K(x)g(u)=\lambda f(x,u)+\mu h(x)\quad &\text{in }\Omega,\\ u> 0\quad &\text{in }\Omega,\\ u=0\quad &\text{on }\partial\Omega,\end{cases}\tag{P\(_{\lambda,\mu}\)} \] where \(\lambda\) and \(\mu\) are positive parameters. Under suitable assumptions on \(K\), \(g\), \(f\) and \(h\) the authors using the maximum principle for elliptic equations establish several existence and nonexistence results for \((\text{P}_{\lambda,\mu})\).