Linear algebra problem with transpose

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To find the formula for (ABx)T, where x is a vector and A and B are matrices, the relevant equation is (AB)T = BTAT. The discussion suggests using this property to derive a simpler expression for (ABx)T without resorting to complex summation notation. It is noted that the approach should consider the properties of matrix multiplication. The conversation highlights the challenge of simplifying the problem, indicating that previous attempts using summations were cumbersome. Ultimately, the goal is to arrive at a cleaner formula for the transpose of the product involving matrices and a vector.
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Homework Statement



Find a formula for (ABx)T, where x is a vector and A and B are matrices of appropriate sizes.

Homework Equations



(AB)T = BTAT among a few others, probably the most relevant one with transposes here.

The Attempt at a Solution



I'm wondering what this "formula" the problem asks for looks like. I know that (ABx)T = xTBTAT but I can't really see how much simpler another formula might be.

Any ideas what route to take to find a formula for this, preferable without the use of a lot of summation notation or anything beyond a beginning linear algebra course? We used a lot of summations earlier trying to tackle this problem and it just looked messy; I'm hoping there may be a cleaner way of approaching the problem.
 
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Perhaps what the question is getting at is for you to use the formula (AB)T = BTAT which you know works for a product of two conformable matrices and get the formula for three of them from that, being careful about properties of matrix multiplication that you know.
 
I got it for three matrices and that was before using all the sums. We didn't really go back to the problem again (she said it was so ugly anyway) so I guess that's it for the problem. :) Thanks
 

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