I1.3 It is given that $f(x)=p x^{3}+q x+5$ and $f(-7)=\sqrt{2} b+1$. Find $c$, if $c=f(7)$.
$\begin{array}{l}p(-7)^{3}+q(-7)+5=\sqrt{2} \cdot 3 \sqrt{2}+1=7 \\ -\left[p(7)^{3}+q(7)\right]=2 \\ c=f(7) \\ \quad=p(7)^{3}+q(7)+5 \\ \quad=-2+5=3\end{array}$