Let P2 be the vector space of all polynomials of degree 2 or less. We can write this as P2 = {a + bx + cx^2 | a, b, c ∈ R}.
Let W be the subset
W = {a + a^2 + a^3 | a ∈ R}.
a) Write down polynomial p(z) that is in W.
b) Write down polynomial q(z) that is in P2 but not in W.
c) Is W a subspace of P3? If yes, show that it is closed under addition and scalar multiplication. If not, show that it fails one of these.
Repeat all three parts of Exercise #2, but use the subset X of P2 given by
X = {a + a^2 + 10a + 10 | a ∈ R}.
Repeat all three parts of Exercise #2, but use the subset U of P2 given by
U = {a^2 + a^3 + (10 + a)x + a | a ∈ R}.