Declension table of ?dṛḍhatvac

Masculine	Singular	Dual	Plural
Nominative	dṛḍhatvaṅ	dṛḍhatvañcau	dṛḍhatvañcaḥ
Vocative	dṛḍhatvaṅ	dṛḍhatvañcau	dṛḍhatvañcaḥ
Accusative	dṛḍhatvañcam	dṛḍhatvañcau	dṛḍhatūcaḥ
Instrumental	dṛḍhatūcā	dṛḍhatvagbhyām	dṛḍhatvagbhiḥ
Dative	dṛḍhatūce	dṛḍhatvagbhyām	dṛḍhatvagbhyaḥ
Ablative	dṛḍhatūcaḥ	dṛḍhatvagbhyām	dṛḍhatvagbhyaḥ
Genitive	dṛḍhatūcaḥ	dṛḍhatūcoḥ	dṛḍhatūcām
Locative	dṛḍhatūci	dṛḍhatūcoḥ	dṛḍhatvakṣu

Compound dṛḍhatvak -

Adverb -dṛḍhatvaṅ