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Fraction rules A/B/C vs B/C/A - Mathematics Stack Exchange

Jan 29, 2018 · I suspect you meant to write $$\frac {\left (\frac BC\right)}A=\frac {B} {CA}$$ which is correct and can be established by multiplying by $\frac CC$. The only clue in what you wrote is the size of the f...

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Proving the identity: (A\\B) ∪ (B\\C) = (A∪B) \\ (B∩C)

Jul 6, 2019 · Then the indicator function of $ (A\setminus B)\cup (B\setminus C)$ is $$ a (1-b)+b (1-c)-a (1-b)b (1-c)=a-ab+b-bc$$ because $$ (1-b)b=b-b^2=b-b=0$$ The indicator function of the right-hand side is $$ (a...