This is from a QM problem. A & B are the unknowns, k and K are given and [itex]i = \sqrt{-1}[/itex]. Use Cramer's rule to find A and show that |A|(adsbygoogle = window.adsbygoogle || []).push({}); ^{2}= 1.

[tex]A - B = -1[/tex]

[tex]ikA - KB = ik[/tex]

I applied Cramer's rule to determine A:

[tex]A = \frac{\left |\begin{array}{cc} -1 & -1 \\ ik & -K \end{array}\right|}{\left |\begin{array}{cc} 1 & -1 \\ ik & -K \end{array}\right|}[/tex]

So, I am left with:

[tex]A = \frac{K + ik}{-K + ik}[/tex]

I am stuck here, because this nowhere resembles the result I want to prove. Just guide me...

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# Homework Help: Help with Cramer's rule

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