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.4 \+ a4 L# v- d, J
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? ) E& X6 G# @+ |+ l4 y$ s U! k) K If an extreme point is optimal, then is it possible that not all z_j-c_j≥0 for an associated basis?% z) F/ V6 @2 f2 Y! {, N- b
If there exists a d such that Ad=0,d≥0, and cd≥0, then is the optimal objective value unbounded? ) g- e8 O/ `: q Let x ̅ be a feasible solution with exactly m positive components. Is x ̅ necessarily an extreme point of X?1 B- ?+ {- Q! v1 l* s8 h
If a nonbasic variable x_k has z_k-c_k=0 at optimality, then can one claim that alternative optimal solutions exist? 6 j) W, K; R" R2 A6 M& i( R& i 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.4 J# \3 ]* k: k3 r
Is it possible for an optimal solution to have more than m positive variables?- `8 D) C& R9 s6 U
Suppose that n=m+1. What is the least upper bound on the number of extreme points and feasible bases? 5 g* U, b0 F! s. L: I5 j* V( B A p-dimensional polyhedron can have at most p extreme directions. True or false? Explain. & |, ~( o6 U+ }% m4 q! l 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.* h2 f- |, s+ P3 N. x0 h, Z3 C
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