Declension table of ?kaṣṭārtha

Masculine	Singular	Dual	Plural
Nominative	kaṣṭārthaḥ	kaṣṭārthau	kaṣṭārthāḥ
Vocative	kaṣṭārtha	kaṣṭārthau	kaṣṭārthāḥ
Accusative	kaṣṭārtham	kaṣṭārthau	kaṣṭārthān
Instrumental	kaṣṭārthena	kaṣṭārthābhyām	kaṣṭārthaiḥ kaṣṭārthebhiḥ
Dative	kaṣṭārthāya	kaṣṭārthābhyām	kaṣṭārthebhyaḥ
Ablative	kaṣṭārthāt	kaṣṭārthābhyām	kaṣṭārthebhyaḥ
Genitive	kaṣṭārthasya	kaṣṭārthayoḥ	kaṣṭārthānām
Locative	kaṣṭārthe	kaṣṭārthayoḥ	kaṣṭārtheṣu

Compound kaṣṭārtha -

Adverb -kaṣṭārtham -kaṣṭārthāt