1   Don't understand an equation  ,
2. I don't understand why , There are uncountable subsets in a separable set ？ thank you

1 yes

2. It's every element in a separable set   An open cover behind the center

all 0 1 The sequence is and all binary decimals     One by one     And all binary decimals can be combined with [0,1] Closed intervals correspond one to one

So it's not countable

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