It means ,every vector of v is a linear combination of elements of the basis ... . ( The elements of v must be linear independent )
I have tried to prove my question , but i coudn't till now ... . my ultimate goal is to prove that for Every proper subspace W of a finite dimensional inner...
suppose that {ei} 1<=i<=n is a basis for v and w is a subspace of v of dimension m<n ... . so Can we always find a basis for w which includes m elements of {ei} 1<=i<=n ?
does always w include m elements of {ei} 1<=i<=n ?