v1,v2,w1,w2 are independant vectors in space V

so Sp{v1,v2)=Sp{w1,w2} and {v1,w2} independant.

prove that {v1,v2} is independant.

before solving this question i got some other questions.

first question:

if {v1,w2} is independant what can i say about the dimention of sp{v1,w2}

i was told that dim sp{v1,w2} >=2

how can it be that two vector can span a dimention bigger then 2?

??

second question

beacause there where only two vectors sp{v1,w2} <=2

so in sum of both thing we get dim sp{v1,w2}=2

cant understand the reason why on the one hand its bigger then 2

and on the other one its smaller then 2

??