(d) Let X1 = [1, 0, -1, 3), X2 = [1, -3, 1, 0)7, and X3 = [0, -1, -3, -1) be vectors in R. (i) Show that {X1, X2, X3} is an orthogonal set. (ii) Find an orthogonal basis R$ that contains X1, X2, X3. (iii) Write the vector X = [3, -2, 2, 7)T as a linear combination of the vectors in your orthogonal basis from (ii). (e) Let U = span { X1, X2, X3), where X1 = [1, -1, -17, X2 = [2, 1, 4]], and X3 = 15, -4, -37 are vectors in R . Using the Gram-Schmidt Algorithm, find an orthonormal basis for the subspace U