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Discrete Math Proof: Solving Homework Equations

Thread starter Bashyboy
Start date Oct 18, 2012
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Discrete Discrete math Proof

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4 replies · 2K views

Bashyboy

Thread starter
Oct 18, 2012

#1

Homework Statement

I attached the problem as a file.

Homework Equations

The Attempt at a Solution

I get stuck on how to properly represent the summation. How does k find it's way as one of the sub-scripts?

Last edited: Oct 18, 2012

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HallsofIvy

Science Advisor

Homework Helper

Oct 18, 2012

#2

Your post makes no sense and there is no attachment.

Bashyboy

Oct 18, 2012

#3

I am so sorry, I'll fix that.

HallsofIvy

Science Advisor

Homework Helper

Oct 18, 2012

#4

Okay, you have B^TA^T. Now, what is (AB)^T?

Bashyboy

Oct 19, 2012

#5

So,

[itex]AB = \sum_k a_{ki}b_{jk}[/itex]

[itex](AB)^t = \sum_k a_{ki} b_{jk} = \sum_k b_{jk} a_{ki} = B^tA^t[/itex]

Does that look correct?

Last edited: Oct 19, 2012

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