Is the rak'ah of a latecomer counted if he catches the Imam bowing and has not recited Al-Fatihah, and should he say one takbir or two?

The latecomer (ma'mum) catches the rak'ah if he joins the Imam in bowing (rukūʿ). His opening takbir (takbīrat al-iḥrām) suffices for the takbir of bowing. It is a condition that he pronounces the opening takbir while standing. If he catches the Imam while he is bowing, the recitation of Al-Fatiha is waived for him, and the rak'ah is counted for him. However, if he can pronounce two takbirs, that is preferable.