Rekenen met wortels https://www.youtube.com/watch?v=balFphokNio
Wortels - worteltrekken https://www.youtube.com/watch?v=MiBlfVcNdSw
Wortels [negatieve wortels] https://www.youtube.com/watch?v=aiw3F6SwHfY
Wortels [benadering en exact] https://www.youtube.com/watch?v=sJL0xmtRjEM