Vermenigvuldigen
Uitleg
https://www.youtube.com/watch?time_continue=22&v=V6GB3ACHKaM
https://www.youtube.com/watch?time_continue=20&v=okyPP1JbifE
https://www.youtube.com/watch?time_continue=22&v=5Uy_3OxD_fc
https://youtu.be/-nMJdTD-LQ8
https://youtu.be/AjGP_YCrzgM
https://www.youtube.com/watch?time_continue=18&v=x6_McaodnLQ
https://www.youtube.com/watch?time_continue=19&v=eOpfuhS3cBc
https://www.youtube.com/watch?time_continue=18&v=-gfVvrv2v5o
https://www.youtube.com/watch?time_continue=20&v=jp4Au0T6iU8
https://www.youtube.com/watch?time_continue=22&v=9L59mbTFVpc