No. Of subsets can be formed from a set

[torpid dome]

Bro, look what I found:

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[torpid dome]

So there's a formula given in my book for finding the number of subsets that can be formed of a set

Basically assume a set A

Then no. Of subsets = 2^(n(a))

And if we look at this another way round

Suppose A={1,2,3,4,.....,n}

Such that n(A)=n

So notice that

If we form combinations, we can find subsets

Firstly by choosing 1 from n

Then adding after choosing 2

And so on

We have to put 0 to for the null set

So

$\sum_{r=0}^n \frac{n!}{r!(n-r)!}$

[warped garden]

Conqueror

[torpid dome]

It means that this series should be equal to 2^n

But is it?

[toxic oak]

It is

[torpid dome]

DANG

Prove it

I mean

Derive it

[toxic oak]

Have you heard of binomial expansion ?

[torpid dome]

Yes

(1+1)^n?

[toxic oak]

Yeah

[torpid dome]

Danggg

@toxic oak I'm gonna close now

+close

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