The root remains ر ض و across these forms. What changes is the governing particle and the resulting inflection.
PersonIndicativeAfter lanAfter lam
3m sgيَرْضَىلَنْ يَرْضَىلَمْ يَرْضَ
3m dualيَرْضَيَانِلَنْ يَرْضَيَالَمْ يَرْضَيَا
3m plيَرْضَوْنَلَنْ يَرْضَوْالَمْ يَرْضَوْا
2f sgتَرْضَيْنَلَنْ تَرْضَيْلَمْ تَرْضَيْ
3f plيَرْضَيْنَلَنْ يَرْضَيْنَلَمْ يَرْضَيْنَ
A written form can look identical in two grammatical moods. Understand the governing particle and distinguish the indicative nūn from the feminine plural pronoun.