Answer the following questions along with a concise explanation with respect to the linear program to maximize cx subject to x∈X={x:Ax=b,x≥0}, where A is m×n of rank m<n. ) x; s$ {5 R7 }4 `' \2 c1 l In a simplex tableau, if z_j-c_j=-7 for a nonbasic variable x_j, what is the change in objective value when x_j enters the basis given that the minimum ratio is 3 in the pivot? + Z! h6 ? R% R4 p1 }3 R( K+ I$ @ If an extreme point is optimal, then is it possible that not all z_j-c_j≥0 for an associated basis? $ N: e0 k3 t% u5 ? If there exists a d such that Ad=0,d≥0, and cd≥0, then is the optimal objective value unbounded?' W$ f* r5 k$ D7 O% }, n
Let x ̅ be a feasible solution with exactly m positive components. Is x ̅ necessarily an extreme point of X?2 u& H# y/ n/ k- j" b- u& U
If a nonbasic variable x_k has z_k-c_k=0 at optimality, then can one claim that alternative optimal solutions exist? 8 Y7 l( B, e4 ?+ X0 N3 A If x_1 and x_(2 )are adjacent points and if B_1 and B_2 are respective associated bases, then these bases are also adjacent. True or false? Explain.6 Q% _' I* b5 |
Is it possible for an optimal solution to have more than m positive variables?4 X% n. m; ?, J
Suppose that n=m+1. What is the least upper bound on the number of extreme points and feasible bases?2 _" K% ^: l) p& L3 Y- U7 X
A p-dimensional polyhedron can have at most p extreme directions. True or false? Explain.- v8 d# g4 _( M' q9 d: w, f
Let x ̅ be an extreme point having (m-1) positive components. Then there are (p+1) bases associated with this extreme point, where p=n-m. True or false? (Assume that Ax=b does not imply any variable to be a constant) Explain. 9 I ?: G) i& x6 g * s/ M& j" c& v2 n