Solution
= Solution
The <integral equation> says precisely $h=L^{-1}z$ with the homogeneous mixed endpoint conditions. Since the supplied $h$ satisfies those conditions, apply $L$ directly:
$$
\boxed{z(x)=Lh=h''+h=x^2-2x+2.}
$$
No <integration> is required. The absence of a zero <eigenvalue> established in (b)–(c) also proves uniqueness of this recovered forcing.