6.2. Consider the problem minimize x1 + (x2)2 + (x3)2 + (x4)2 x4 subject to Zn + x2 + x3 + 4x4 2 8 x1+2x2+2x3+x4 =6 x20. At the point x = (l, l, l, I) treat (x1, 3:2) as basic variables and (x3, x4) as super basic variables. Carry out one iteration of the reduced gradient method