you may use Gram-Schmidt Process.
See Gram?Schmidt process - Wikipedia, the free encyclopedia
I am having great trouble finding a matrix A which has a specified nullspace (the span of 4 vectors in R5, of which 3 are linearly independent). I know row(A) null(A) but it doesn't seem to help me at all and I get nowhere towards the solution. Any tips for tacking such a problem?
you may use Gram-Schmidt Process.
See Gram?Schmidt process - Wikipedia, the free encyclopedia