How Do You Calculate the Determinant of a 5x5 Matrix?

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    Determinant Matrix
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Discussion Overview

The discussion revolves around calculating the determinant of a 5x5 matrix. Participants explore various methods and seek clarification on the concept of determinants, including definitions and theorems related to them.

Discussion Character

  • Homework-related
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses uncertainty about how to find the determinant of a specific 5x5 matrix and requests guidance.
  • Another participant asks for the definition of a determinant and inquires about relevant theorems.
  • A third participant shares a link to a resource that presumably contains information on determinants.
  • One participant suggests a preferred method of calculating determinants by row-reducing to a triangular matrix, noting that the determinant of a triangular matrix is the product of its diagonal elements. They also mention conditions under which the determinant becomes zero.
  • Another participant questions whether a numerical answer is needed or if the steps of computation are required, suggesting that the original poster should have been taught the technique for calculating determinants.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the preferred method for calculating the determinant, as multiple approaches are discussed. The need for clarification on definitions and theorems indicates uncertainty in understanding the concept.

Contextual Notes

Some participants reference external resources for definitions and methods, indicating that there may be varying levels of familiarity with the topic among participants. The discussion does not resolve the question of which method is best or most appropriate for the given matrix.

Who May Find This Useful

Students or individuals seeking to understand how to calculate the determinant of larger matrices, as well as those interested in different methods of matrix manipulation and determinant properties.

babygirl_28
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i have a problem that i need to find the determinant of a 5x5 matrix. i have no clue how to go about solving this problem

2, -9, 1, 8, 4
-10, -1, 2, 7, 0
0, 4, -6, 1, -8
6, -14, 11, 0, 3
5, 1, -3, 2, -1
 
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babygirl_28 said:
i have a problem that i need to find the determinant of a 5x5 matrix. i have no clue how to go about solving this problem

2, -9, 1, 8, 4
-10, -1, 2, 7, 0
0, 4, -6, 1, -8
6, -14, 11, 0, 3
5, 1, -3, 2, -1

What's the definition of a determinant?? What theorems did you see??
 
There are a number of different ways to calculate a determinant. The method I personally prefer is to row-reduce a triangular matrix. As long as you use only "add a multiple of one row to another", you wil always have matrices with the same determinant. And the determinant of a triangular matrix is just the product of the numbers on the diagonal. Of course, if you get a "0" on the diagonal, you can stop- the determinant is 0.

You never have to use "swap two rows" or "multiply/divide a row by a number" but if you do to simplify the arithmetic, whenever you swap two rows, you need to multiply the final result by -1 to get the correct determinant and whenever you multiply/divide a row by a number, you need to divide/multiply the row by that number to get back to the correct determinant.
 
Do you need a numerical answer?
If so, there are many free calculators available that would do it.

Or do you need to work through all the steps of its computation?
If you've been asked to do something, you should have been first taught the technique for doing so. If not, the reference already recommended, plus Wikipedia or MathWorld, offer good introductory material.
 

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