Prove that (9.147) implies (x l), (x m) = 0 for all l m. (4(x), 4(x m)) = 4(x) 4(x m) dx

Prove that (9.147) implies φ(x − l), φ(x − m) = 0 for all l ≠ m.

(4(x), 4(x m)) = 4(x) 4(x m) dx = 0 for all m = 0. (9.147)