Prob. 1. Let A1 =
a) Prove or disprove: (i) Y ∈ SP(A1, A2, A3);
(ii) Z ∈ Sp(A1, A2, A3)
b) FIND a basis for Sp(A1, A2, A3).
Prob. 2. Let V = P3 be the space of cubic polynomials. Let e1 (t) = t3; e2(t) = t2(1 - t); e3(t) = t(1 - t)2; e4(t) = (1-t)3.
SHOW that every v ∈ P3 has a unique representation v = i=1Σ4 ciei(t)
Prob. 3. Let BN = set of all linear combinations of eikt k = -N,........,0.......N. (Such linear combinations form a set of "band limited" functions. They play a central role in Fast Fourier Transforms and in digital signal processing, among other things.) It is easy to see that Bay is a vector space of functions. Assume that this is so.
a) SHOW {1, cost, cos Nt, sint ....... sin Nt} is a basis for BN
b) What is Dim(BN)?
Prob. 4. V = Sp (1, cost, cos 2t, cos3t, cos 4t) is a vector space.
a) SHOW {1, cos t, cos2t, cos3t, cos4t is a basis for V
b) What is Dim (V)?
Prob. 5. Let V be the vector space of all 2 x 2 matrices over the real numbers. PROVE that V has dimension 4 by exhibiting a basis for V which has four elements.
Prob. 6. Let V and W both be subspaces of a given vector space. PROVE or DISPROVE: Their intersection V ∩ W(= {x : x ∈ V and x ∈ W}) is also a subspace. (Remember, there are at least three facts you have to consider.)