Solving Matrix: AX + B = CA | X + A'B = C

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TranscendArcu
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Homework Statement



Skjermbilde_2012_03_08_kl_11_13_40_AM.png


The Attempt at a Solution



I think I'm oversimplifying this problem. Why can't I just write:

AX + B =CA
X + A'B = C
X = C - A'B

?
 
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does your notation mean [itex]A' = A^{-1}[/itex]?

... if so, you can't do what you propse because matrix multiplication does not necesarrily commute. ionce you fix that, you're not far off the answer
 
Yes, that's what I intended my notation to convey.

Do I have to write:

AX + B = CA
AX = CA - B
A'(AX) = A'(CA - B)
IX = A'CA - A'B
X = A'CA - A'B

?
 
TranscendArcu said:
AX + B =CA
X + A'B = C
X = C - A'B

lanedance said:
does your notation mean [itex]A' = A^{-1}[/itex]?

The notation A' is sometimes used to mean the transpose of matrix A. For inverses, I don't think I've ever seen ' used to indicate the inverse.

It's just as easy to write an exponent of -1 as an exponent of 2 or 3, and the intent is much clearer.

At the bottom of the input pane, click the Go Advanced button. This opens a menu of icons at the top of the input pane. The X2 button let's you write exponents, which it does by inserting [ sup ] and [ /sup ] tags (without the spaces).

You can also do this manually, like so: A[noparse]-1[/noparse]. I have inserted some other tags so that you could see the sup tags. Without those other tags, what I wrote renders like this: A-1.