[Machine] About the one who doubts his prayer, he does not know whether he prayed three or four rak'ahs, both of them said: "Let him stand and pray another rak'ah and then perform two prostrations if he prayed."
عَنِ الَّذِي يَشُكُّ فِي صَلَاتِهِ فَلَا يَدْرِي أَثْلَاثًا صَلَّى أَمْ أَرْبَعًا فَكِلَاهُمَا قَالَا فَلْيَقُمْ فَلْيُصَلِّ رَكْعَةً أُخْرَى وَلْيَسْجُدْ سَجْدَتَيْنِ إِذَا صَلَّى
Yahya related to me from Malik from Afif ibn Amr as-Sahmi that Ata ibn Yasar said, "I asked Abdullah ibn Amr ibn al-As and Kab al Ahbar about someone who was uncertain in his prayer, and did not know whether he had prayed three or four rakas. Both of them said, 'He should pray another raka and then do two sajdas from the sitting position.' "
عَنِ الَّذِي يَشُكُّ فِي صَلاَتِهِ فَلاَ يَدْرِي كَمْ صَلَّى أَثَلاَثًا أَمْ أَرْبَعًا فَكِلاَهُمَا قَالَ لِيُصَلِّي رَكْعَةً أُخْرَى ثُمَّ لِيَسْجُدْ سَجْدَتَيْنِ وَهُوَ جَالِسٌ