In: Math
Solve 4 questions of quiz. each of them gives 0.25 point
1. Show that the following sets of elements in R3 form subspaces. (a). The set of all (x, y, z) such that x − 2y + z = 0. (b). The set of all (x, y, z) such that x = 3z and y = z.
2. (a). Let U = {(x, y) ∈ R2 : 0 ≤ x ≤ 1 and 0 ≤ y ≤ 1} and W = {(x, y) ∈ R2 : x 2 + y 2 ≤ 1}. Are these sets subspaces of R^2? (b). Find the sum U + W.
3. If U and W are subspaces of a vector space V, show that U + W is a subspace
4.Show that functions f(t) = t and g(t) = 1/t defined for t > 0 are linearly independent.