Formula_1775

\[\begin{gathered}\hat{f}_{p q} u(x)=(2 \pi \hbar)^{-n} \int e^{\frac{i}{\hbar} p \cdot(x-y)} f(p, y) u(y) d y \\\hat{f}_{q p} u(x)=(2 \pi \hbar)^{-n} \int e^{\frac{i}{\hbar} p \cdot(x-y)} f(p, x) u(y) d y .\end{gathered}\]