Simple Matrices proof using Mathematica help

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The discussion centers on proving the matrix identity (AB)^-1 = B^-1 A^-1 using Mathematica for arbitrary 3x3 matrices A and B. The user successfully verified the transpose identity but encountered issues with the inverse identity, as Mathematica returns expanded matrices instead of "True" or "False." Suggestions include checking the syntax of the inverse function and noting that rounding differences may affect results. The user suspects that the discrepancy arises from how Mathematica handles matrix inverses differently in calculations. The conversation highlights the challenges of verifying matrix properties in computational software.
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Simple Matrices proof using Mathematica help!

Homework Statement



Hey guys, I'm trying to prove that

(AB)-1 = B-1 A-1
and also the one that looks the same but is with transpose of the matrices

making A and B arbitrary 3x3 matrices. I made

A = {{a_1,a_2,a_3}...}
B = {{b_1,b_2,b_3}...}

and I was able to prove the Transpose one by typing "Transpose[A B] == Transpose * Transpose[A] " and it spit out the word "True"

However, when I write "Inverse[A B] == Inverse Inverse[A] ", it does not spit out the word true, rather it spits back out the matrices expanded. Does anyone know how to tweak it so that it'll spit out either the words true or false? Thanks


Homework Equations





The Attempt at a Solution

 
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making A and B arbitrary 3x3 matrices.
... and checking that the inverse exists?
when I write "Inverse[A B] == Inverse Inverse[A] ", it does not spit out the word true
check syntax - did you write the above or did you write:

Inverse[A B] == Inverse*Inverse[A]

(I can't remember if it matters)

I find that the inverse function does some rounding off, and the rounding is different if I do inverse[A*B] and when I do inverse[A]*inverse, so whenever I do Inverse[A*B] == Inverse*Inverse[A] it returns "false".
 
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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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