f [ψ] = f [ψ] + * = ψ / f [ψ] = f [ψ] + * = ψ / / f [ψ] = f [ψ] + * = ψ / / f [ψ] = f [ψ] + * = ψ / / f [ψ] = f [ψ] + * = ψ / d ψ f [ψ] = f [ψ] + * = ψ / / d ψ f [ψ] = f [ψ] + * = ψ / / d ψ f [ψ] = f [ψ] + * = ψ / ...