If $f:[-6,6] \to \Re$ is defined by $f(x)=x^2-3$ for $x \in \Re$, then $(f0f0f)(-l)+(f0f0f)(0)+(f0f0f)(l)=$

Question

$$\begin {array} {1 1} (1)\;f(4 \sqrt 2) & \quad (2)\;f(3 \sqrt 2) \\ (3)\;f(2 \sqrt 2) & \quad (4)\;f(\sqrt {2}) \end {array}$$