Originally Posted by

**jkong** I am struggling with a few homework problems.

1. a) Show that the set of nonsingular 2x2 matrices is not a subspace of M2x2.

b) Show that the set of singular 2x2 matrices is not a subspace of M2x2.

(Let M2x2 be the vector space of all 2x2 matrices for both)

2. Describe the smallest subspace of M2x2 that contains

(1 0) (1 0)

(0 0) and (0 1) then find dimension of the subspace.

3. Let B = {1 + t - 2t^2, t - t^2, 2 - 2t + t^2}. Check that B is a basis for P2 and find [3 + t - 6t^2]b.