(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

in addition to those provided in the questions, I used the following:

Tr(B) = sigma<x_j|B|x_j>

purity = Tr(rho^2)

3. The attempt at a solution

I find calculating trace and purity very confusing. Am I on the right track with question 1? With question 2, I am really unsure about how to proceed further. Any help would be greatly appreciated.

Thanks in advance.

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# Homework Help: QM: Purity, two-outcome measurements

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