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Using the Simplex Algorithm, solve the following problem (The Simplex Algorithm is available in the appendix of the book by Snyman (or the Lecture Notes from Prof Ali) if you are not familiar with it). The Simplex Algorithm is one of the first algorithms which was developed for Linear Programming problems, it is classic and an appreciation of how it works is desirable:

(P ₁) { max 3x₁+2x ₂+4x ₃
subject to x₁+x ₂+2x ₃ ≤4;
2x₁+3x ₃ ≤5;
2x₁+x ₂+3x ₃ ≤7;
x₁,x ₂,x ₃x ≥0;




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Final answer:

The Simplex Algorithm involves setting up a Simplex tableau, performing pivot operations to optimize the objective function subject to constraints, and interpreting the final tableau to reach the maximum value. Careful algebraic steps are essential throughout the process.

Step-by-step explanation:

The Simplex Algorithm is a method for solving linear programming problems. The goal of the algorithm is to maximize or minimize a linear function subject to a set of linear inequalities (constraints). Here's a step-by-step explanation of how you would use the Simplex Algorithm to solve the provided linear programming problem:

  1. Identify the objective function and the constraints of the problem.
  2. Convert the constraints into equalities by introducing slack variables and set up the initial simplex tableau.
  3. Identify the entering variable (with the most positive coefficient in the objective function row) and the leaving variable (by the smallest non-negative ratio test).
  4. Perform pivot operations to transform the tableau, maintaining the basic feasible solution.
  5. Repeat the process until no further improvements can be made, which is when there are no positive coefficients in the objective function row in the tableau.
  6. Interpret the final tableau to get the maximum value of the objective function and the values of the variables at that maximum.

More specifically, our example would involve setting up the initial Simplex tableau with the given constraints and the objective function of 3x₁ + 2x₂ + 4x₃. You will need to add slack variables to turn the inequalities into equalities. After the tableau is set up, you pivot around the entry with the highest coefficient in the last row, then proceed to find the row to pivot with using the least ratio test. The process continues iteratively until no coefficients in the objective row are positive, suggesting that the solution is optimal.

Checking and rechecking each algebraic step carefully is crucial, as errors in pivot operation can lead to an incorrect solution. Remember to also verify that your solution is reasonable in the context of the problem.

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