- prover commit to \(f(x)\)
$$f(X)=f_E(X^2)+X\cdot f_O(X^2)$$
if we take an intermediate variant \(Y\) to replace the \(X^2\)
With a fixed \(Y\), then \(f(x)\) can be considered as one degree polynomial for \(X\), as
$$f(X)=f_E(Y)+X\cdot f_O(Y)$$
and for a given \(y\), it determineds a unique line (one degree polynomial)
and the …