Your Help is greatly appreciated. Thanks in advance. I am having a hardtime with these three problems.
1) Find the basis for Nullspace of A if A equals
1 2 -3
2 1 0
-2 -1 3
2) Let W be the subspace of R^(4) spanned by vectors (1,-2,5,3)^(T),
(2,3,1,-4)^(T), (3,8,-3,-5)^(T). Extend the basis of W to a basis of the whole space of R^(4).