For $\lambda \in \mathbb{R}$, consider the boundary value problem $$\left. \begin{matrix} x^2 \frac{d^2y}{dx^2}+2x\frac{dy}{dx}+\lambda y=0, & x\in [1,2] \\ y(1)=y(2)=0 & \end{matrix} \right \rbrace \quad - (P_\lambda)$$ Which of the following statement is true?
1. There exists a $\lambda_0 \in \mathbb{R}$ such that $(P_\lambda )$ has a nontrivial solution for any $\lambda >\lambda_0$
2.  $\lambda \in \mathbb{R} : (P_\lambda )$  has a nontrivial solution is a dense subset of $\mathbb{R}$
3. For any continuous function $f:[1,2] \rightarrow \mathbb{R}$ with $f(x) \neq 0$ for some $x\in [1,2]$, there exists a solution $u$ of $(P_\lambda )$ for some $\lambda \in \mathbb{R}$ such that $\int_{1}^{2}fu\neq 0$
4. There exists a $\lambda \in \mathbb{R}$ such that $(P_\lambda)$ has two linearly independent solutions.