Should a latecomer (masbuq) say "Allahu Akbar" when standing to make up for what he missed if he caught the last tashahhud, or the prostration, or a complete rak'ah?

If a latecomer catches the last rak'ah, he should not say takbir when standing up to make up for what he missed. However, if he joins the Imam during the final tashahhud, or if he does not catch a complete rak'ah with him, then he should say takbir when standing up to make up for what he missed. The questioner is advised to disregard whispers and not pay attention to them.