Easy to see that these two determinants are identical

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SUMMARY

The discussion centers on demonstrating the equality of two determinants without expanding them. The determinants in question are structured as follows: the first determinant consists of the rows (bc, a^2, a^2), (b^2, ca, b^2), and (c^2, c^2, ab), while the second determinant comprises the rows (bc, ab, ca), (ab, ca, bc), and (ca, bc, ab). Participants noted that both determinants share identical diagonal values, leading to the conclusion that they are indeed equal, fulfilling the requirement of the homework statement.

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Homework Statement


Without expanding the determinant show that
bc a^2 a^2
b^2 ca b^2
c^2 c^2 ab

=
bc ab ca
ab ca bc
ca bc ab

Homework Equations


3. Attempt at solution
Well, one thing I noticed is that the diagonal row all contain the same values (bc, ca, ab)
Using the first determinant, we can simplify it to
bc |ca b^2| - ca|bc a^2| + ab |bc a^2|
...|c^2 ab|...|c^2 ab|...|b^2 ca|

the second determinant would be
bc |ca bc| - ca |bc ca| + ab|bc ab|
...|bc ab|...|ca ab|...|ab ca|obviously its easy to see that these two determinants are identical, but is this what the question asks? It says to show without expanding, so I'm not sure if there's another way to show this.
 
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Your original determinant is somewhat garbled. You can insert text with
Code:
 tags to help preserve spacing.
 
my bad, that should be easier to read now.
 

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