V is a vectoric space.

$\displaystyle W_1,W_2\subseteq V\\$

$\displaystyle W_1\nsubseteq W_2\\$

$\displaystyle W_2\nsubseteq W_1\\$

prove that $\displaystyle W_1 \cup W_2$ is not a vectoric subspace of V.

i dont ave the shread of idea on how to tackle it

i only know to prove that some stuff is subspace

but constant mutiplication

and by sum of two coppies

this question here differs a lot