What is the Pattern for Determinants of Matrices with Repeating Variables?

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SUMMARY

The discussion focuses on identifying patterns in the determinants of matrices with repeating variables, specifically for 2x2 and 3x3 matrices. The determinant for the 2x2 matrix |1 1| |x y| is established as y - x. For the 3x3 matrix |1 1 1| |x y z| |x² y² z²|, the determinant is expressed as xy² - yx² - xz² + zx² + yz² - zy². The participants explore the possibility of factoring this determinant and suggest that a discernible pattern exists for larger matrices, such as 4x4 and 5x5, following the form (1, x, x², x³, etc.).

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  • Understanding of matrix determinants
  • Familiarity with polynomial factorization
  • Knowledge of algebraic expressions involving variables
  • Basic concepts of linear algebra
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Students and educators in mathematics, particularly those studying linear algebra, matrix theory, and polynomial functions, will benefit from this discussion.

astonmartin
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Homework Statement



Alright so apparently there is some pattern in finding these determinants:

for the 2x2, the determinant of
|1 1|
|x y| is y - x

for 3x3, the determinant of

|1 1 1 |
|x y z |
|x^2, y^2, z^2| xy^2 - yx^2 - xz^2 +zx^2 + yz^2 - zy^2

Apparently that can be factored (not sure how), and using the roots, there will be a pattern that you can observe for finding a determinant of a 4x4, 5x5, etc of the same form (1, x, x^2, x^3, etc.)

How do you factor the 3x3 determinant, and what is the pattern?

Thanks!
 
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