Can somebody help with this matrix problem?

Complex numbers, rational functions, logarithms, sequences and series, matrix operations, etc.
littlebu
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Re: Can somebody help with this matrix problem?

Postby littlebu » Tue Dec 07, 2010 10:03 pm

I got the four equations as

a - b = -5
c -d = 7
4b = -4
4d = 12

solving these I get A as

A = [-6 -1]
A = [10 3]

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stapel_eliz
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Postby stapel_eliz » Wed Dec 08, 2010 11:52 am

littlebu wrote:I got the four equations as

a - b = -5
c -d = 7
4b = -4
4d = 12

Excellent! That's exactly right. Then:

. . . . .4b = -4, so b = -1
. . . . .a - (-1) = -5, so a = -6
. . . . .4d = 12, so d = 3
. . . . .c - (3) = 7, so c = 10

And then you can quickly check:



. . . . .

Since the matrices multiply to the desired result, this confirms that your answer is correct. Good work! :wink:


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