CBSE Class 11-science Answered
this can be connected to the binimial theorem easily .
the subserts of a given set S may have 0 elements, 1 element, 2 elements....n elements.
so number of subsets will be
sum of all these will be the same as the expansion of (1+1) whole raised to power n, which is eequal to 2 raised to n
hence the answer.