Don't have Telegram yet? Try it now!
https://jjthetutor.com/show-that-if-fr-the-xaxis-and-y-axis-are-subspaces-of-r2-plane-but-th-union-of-these-two-axis-is-not-a-subspace/
Show that if F=R the x=axis and y-axis are subspaces of R2 plane but th union of these two axis is not a subspace