Matrix Calculation Error: Finding the Correct Solution

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The discussion centers on a matrix calculation error in a homework problem, where the user arrives at a different solution than the one provided in the textbook. The user details their method, which involves multiplying by √2 and solving a system of equations derived from the matrix. They find that their calculations lead to a specific value for d, which they claim is actually the value for c. The user asserts that the textbook's solution is incorrect, as it does not satisfy the original equation when substituted. The conversation highlights the importance of verifying solutions in matrix calculations.
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Homework Statement



See attached image.

The Attempt at a Solution



I get a different solution: First multiply by \sqrt{2}, then {1 \choose -1} = {c + d \choose ci - di}. So we get c + d = 1 and so (1 - d)i - di = -1. Solving the last one gives 2di = 1 + i, so d = \frac{1 + i}{2i} = \frac{1 + i}{2i}\frac{i}{i} = \frac{i - 1}{-2} = \frac{1 - i}{2}. But that's the answer for c. Where does my solution go wrong?
 

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The book is wrong. You can see this by substituting their "solution" into the original equation.
 
Thanks.
 
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