Let h denote the plane in r^3 that is given by the equation 3x - 2y + z = 0. let x denote the point with coordinates (2, 1, -1). a) compute the orthogonal projection of x onto h. check that the result px lies on h and that (x-px) is perpendicular to h. b) find the reflection of x across h. c) find the standard matrices for the orthogonal projection onto h and the reflection across h. state the matrices in the form a = (1/m) b where m is an integer and b is a matrix with integer entries.