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📐 Mathematics  ·  Linear Programming  ·  JEE

Subject to x + y ≤ 4 with x, y ≥ 0, the maximum of Z = x + 2y is:

Answer: 8.

  • A 4
  • B 6
  • C 8
  • D 12

Correct answer: C. 8

Explanation: The maximum is at (0, 4), giving Z = 8.

Feasible Region and Corner PointsxyOABCfeasible regionZ = ax+by is evaluated ONLY at corners O, A, B, C - the optimum is always at one of these

The feasible region (shaded) is bounded by the constraint lines; the fundamental theorem of LPP guarantees the optimal value of the objective function occurs at one of the corner points (O, A, B, C), so only these need to be checked, not the entire region.

Concept context

Optimizing a linear objective function subject to linear constraints using the graphical corner point method.

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