Declension table of ?ṛtavya

Masculine	Singular	Dual	Plural
Nominative	ṛtavyaḥ	ṛtavyau	ṛtavyāḥ
Vocative	ṛtavya	ṛtavyau	ṛtavyāḥ
Accusative	ṛtavyam	ṛtavyau	ṛtavyān
Instrumental	ṛtavyena	ṛtavyābhyām	ṛtavyaiḥ ṛtavyebhiḥ
Dative	ṛtavyāya	ṛtavyābhyām	ṛtavyebhyaḥ
Ablative	ṛtavyāt	ṛtavyābhyām	ṛtavyebhyaḥ
Genitive	ṛtavyasya	ṛtavyayoḥ	ṛtavyānām
Locative	ṛtavye	ṛtavyayoḥ	ṛtavyeṣu

Compound ṛtavya -

Adverb -ṛtavyam -ṛtavyāt