Hello,

I can give you the solutions, and let you do the proof ! That's a good exercise.

(and this is also because I don't know how to do it )

V is a linear combination of V1,V2,.....,Vk

Hmm dim(W1)<dim(W2)2) State and prove a relationship involving dim(W1) and dim(W2), in the case where they dont equal each other.