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Question
Show that the minimum of Z occurs at more than two points.
Maximise Z = x + y, subject to x – y ≤ –1, –x + y ≤ 0, x, y ≥ 0.
Solution
The system of constraints is:
x - y ≤ -1 ....(i)
- x + y ≤ 0 ....(ii)
x, y ≥ 0 ....(iii)
Let l1 : x - y = -1
l2 : -x + y = 0
Clearly, there is no feasible region
[∵ There is no common region]
Hence, there is no maximum value of Z.
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