Prove Theorem 26.3. Hint: With the notation                             Kn(x, z) = Khn (x − z) we copy the proof of Theorem 26.2 such that the only difference is the covering lemma (Lemma 23.6)...

Prove Theorem 26.3. Hint: With the notation

                            Kn(x, z) = Khn (x − z)

we copy the proof of Theorem 26.2 such that the only difference is the covering lemma (Lemma 23.6)

moreover, instead of Lemma 23.2, we refer to Lemma 23.9.