nC0+nC1+nC2+..................+nCn=2^n(adsbygoogle = window.adsbygoogle || []).push({});

in the analytic proof for this my books say that it is the total number of combinations of n different things taken at least 1 at a time.

they say that each object can be dealt in 2 ways, either it can be accepted or it can be rejected.

hence n objects can be dealt in 2^n ways.

but how in selection how does the question of rejection come?what is the significance of this rejection?please explain.

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# Understanding a special combination

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