General vector spaces Let V1,V2,V3 span a vector space V. Show that the Vector V1,V1+V2,V1+V2+V3 also span V. Solution Let V1 = p, V2=q, V3=r As they span, we may write ap+bq+cr = O where O is the zero element of V and the above relation holds only for a=b=c =0 for any a,b,c Now k(v1)+l(v1+v2)+m(v1+v2+v3)=O => (k+l+m)v1 +(l+m)v2+nv3=O => k+l+m=0 , l+m =0 , n=0 => k=l=m =0 => they are linearly independent with same dimension of the basis => new set of vectors also span V.