Question

Fie paralelogramul ABCD ca vectorii u=AC+3BD si v=CA+3AD sunt coliniari

Answer 1

u=AC+3BD=AC+3(BA+AD)=AC+3(CD+AD)=AC+3CD+3AD=

=AC+3(CA+AD)+3AD= - CA+3CA+3AD+3AD

u=2CA+6AD=2(CA+3AD)

v=CA+3AD ⇒ u=2v, ⇒ u si v sunt coliniari