Does $(A^T)^2=(A^2)^T$ for $2\times 2$ matrices?

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In summary, the equation (A^T)^2=(A^2)^T compares the transpose of a matrix A multiplied by itself <sup>2</sup> to the transpose of A squared. It is proven through the properties of matrix multiplication and transposition and is only true for square matrices. This equation is significant because it shows that the order of operations does not matter when taking the transpose and squaring a matrix, making it useful in various real-world applications such as physics, engineering, computer science, data analysis, and cryptography.
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karush
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this is a c/p from my overleaf DE hw

but on proving this I only used a $2\times 2$ matrix

Also I thot $A^2$ meant A(A) a composite but the calculators just multiplied it.typos maybe:rolleyes:
 

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If you think of a matrix as an operator, then matrix multiplication is functionally equivalent to composition. Recall that $(AB)^T=B^T A^T,$ so that
$$\left(A^T\right)^2=A^TA^T=(AA)^T=\left(A^2\right)^T.$$
 

FAQ: Does $(A^T)^2=(A^2)^T$ for $2\times 2$ matrices?

Does (A^T)^2=(A^2)^T hold for all matrices A?

Yes, this property holds for all square matrices A.

Can this property be extended to non-square matrices?

No, this property only holds for square matrices since the transpose operation is only defined for square matrices.

How can this property be proven?

This property can be proven using the definition of matrix multiplication and the properties of transpose operation.

Does this property hold for matrices with complex entries?

Yes, this property holds for matrices with complex entries as well.

Are there any other properties related to this one?

Yes, there are other properties related to this one such as (A+B)^T = A^T + B^T and (AB)^T = B^T A^T.

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