Declension table of akartavya

Neuter	Singular	Dual	Plural
Nominative	akartavyam	akartavye	akartavyāni
Vocative	akartavya	akartavye	akartavyāni
Accusative	akartavyam	akartavye	akartavyāni
Instrumental	akartavyena	akartavyābhyām	akartavyaiḥ
Dative	akartavyāya	akartavyābhyām	akartavyebhyaḥ
Ablative	akartavyāt	akartavyābhyām	akartavyebhyaḥ
Genitive	akartavyasya	akartavyayoḥ	akartavyānām
Locative	akartavye	akartavyayoḥ	akartavyeṣu

Compound akartavya -

Adverb -akartavyam -akartavyāt