Find the matrix of the following transformations:
(a) Multiplication of the point (x, y, z) in ℝ^3 to give the point (x - y, y + 2z, x + z)
(b) Reflection of points in ℝ^2 across the line in y = x.
(a) Multiplication of the point (x, y, z) in ℝ^3 to give the point (x - y, y + 2z, x + z)
(b) Reflection of points in ℝ^2 across the line in y = x.