And if that occurs in the Morning (Subh) prayer, then when he stands for the second rak'ah, he should recite the Opening of the Book (Fatihat al-Kitab) twice, and two surahs, and likewise if it were in the Maghrib prayer; he forgot in the beginning of the first rak'ah, so he recites twice in the second.
And it has been reported from 'Umar ibn al-Khattab that he forgot the recitation in the first rak'ah, so when he was in the second rak'ah, he recited the Opening of the Book twice and recited two surahs."
Chapter: One who misses a prayer in which recitation is performed aloud, then makes it up during the day
• I heard Ahmad ibn Hanbal say—regarding a man who missed a prayer in which recitation is performed aloud in congregation, and he prayed it alone—; he said: "If he wishes, he need not recite aloud, because the [prescribed] aloud recitation is for the congregation." I said: And likewise if a man missed a night prayer in which recitation is performed aloud, and he makes it up during the day? He said: "Yes."
• I heard Ishaq say: "If a man forgets the Maghrib, 'Isha', or Fajr prayers, and makes them up during the day, he should recite aloud; he should make his ears hear it."
849 - 'Ubaydullah ibn Mu'adh narrated to us, saying: I heard Bishr ibn al-Mufaddal say: "If he forgets a prayer in which recitation is performed aloud, and remembers it at a time when recitation is not performed aloud, he should recite aloud. And if he forgets a prayer in which recitation is not performed aloud, and remembers it at night, he should recite aloud."
850 - 'Abd al-Rahman ibn Muhammad al-Tarsusi narrated to us, saying: Abu Usamah narrated to us, from Abu 'Umays, from Mughirah ibn Hakim al-San'ani, from 'Umar ibn 'Abd al-'Aziz—regarding a man who misses part of an obligatory prayer in which recitation is performed aloud—; he said: "When he stands to make it up, he should recite aloud."
(1) Thus it is in the original, and it is possible that there is an omission of the word "lam" (not).