Should the worshipper say "Allahu Akbar" upon rising from prostration in the second rak'ah if the imam has already risen and begun reciting, or should he remain silent?

It is prescribed for the worshiper praying behind an Imam to begin the takbir of transition (takbirat al-intiqal) as they start rising from prostration, and to complete it as they fully stand up, so as to listen attentively to the Imam's recitation. This is because the dhikr (remembrance) for transition is the takbir. And since listening attentively to the Imam's recitation is commanded in Allah's saying: "And when the Qur'an is recited, then listen to it and pay attention that you may receive mercy," the takbirs of transition are obligatory according to the Hanbalis, and the prayer becomes invalid by abandoning them. They are, however, recommended according to the majority of scholars, and the prayer does not become invalid by abandoning them.