Where does “доказываться” come from?

доказываться (Russian) comes from Russian дока́зывать, from Russian доказа́ть, from Russian каза́ть, from Proto-Slavic kāzàti, from Proto-Indo-European kʷeǵ-, from Proto-Indo-European kʷeḱ- — to see; to look.

Ancestry of “доказываться”, step by step

StepLanguageWordMeaning
1Russianдока́зыватьto prove, to demonstrate
2Russianдоказа́тьto prove, to demonstrate
3Russianказа́тьto show
4Proto-Slavickāzàtito show
5Proto-Indo-Europeankʷeǵ-—
6Proto-Indo-Europeankʷeḱ-to see; to look
Every word from Proto-Indo-European kʷeḱ- →Every word from Proto-Indo-European kʷeǵ- →Every word from Proto-Slavic kāzàti →