Proving Symmetry of (A)(A^T) Matrix w/ Tensor Notation

AI Thread Summary
The discussion focuses on proving that the product of a matrix and its transpose, (A)(A^T), results in a symmetric matrix using tensor notation. The solution presented defines P as the product of A and its transpose, leading to the expression p_ik = (a_ij)(a_jk). By manipulating the indices and applying the properties of transposition, it is shown that p_ik equals p_ki, confirming the symmetry. The proof appears to be correct based on the tensor notation used. Overall, the argument effectively demonstrates the symmetry of the matrix product.
neelakash
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Homework Statement



We are to show that (A)(A^T) is a symmetric matrix using tensor notation.

Where ^T denotes TRANSPOSE

Homework Equations


The Attempt at a Solution



I did it in the following way:
Let P=(A)(A^T)
Then,
p_ik=(a_ij)(a_jk) Where A=a_ij and A^T=a_jk
=(a_jk^T)(a_ji)
=(a_kj)(a_ji)
=p_ki

hence proved.
Please tell if I am correct.
 
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It seems right.
 
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