deletions | additions       diff --git a/For_any_set_A_show__.tex b/For_any_set_A_show__.tex  index d7c6075..a64c810 100644  --- a/For_any_set_A_show__.tex  +++ b/For_any_set_A_show__.tex 
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For any set A, show there is a one-to-one correspondence between the $\mathcal{P}(A)$ of all subsets of A and the set $2^A$ of all functions $\alpha: A\to \{0,1\}$. (Hint: use the indicator function of a set).  P(A) $\leftarrow$ (0,1)  \[ \int_-\inf^b \int_-\infty^b  2^A + \int_b^a 2^A + \int_b^\inf \int_b^\infty  2^A \] \[ \left\{  \begin{array}{ll}