A set contains 2n + 1 elements. The number of | vedclass

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Question

(d) Let the original set contains $(2n + 1)$ elements, then subsets of this set containing more than $n$ elements, i.e., subsets containing $(n + 1)$

Vedclass · Accepted Answer

${2^{2n}}$

Vedclass · Answer

(d) Let the original set contains $(2n + 1)$ elements, then subsets of this set containing more than $n$ elements, i.e., subsets containing $(n + 1)$ elements, $(n + 2)$ elements, &hellip;&hellip;. $(2n + 1)$ elements.

$	herefore$ Required number of subsets

$ = {\,^{2n + 1}}{C_{n + 1}} + {\,^{2n + 1}}{C_{n + 2}} + .... + {\,^{2n + 1}}{C_{2n}} + {\,^{2n + 1}}{C_{2n + 1}}$

$ = {\,^{2n + 1}}{C_n} + {\,^{2n + 1}}{C_{n - 1}} + ... + {\,^{2n + 1}}{C_1} + {\,^{2n + 1}}{C_0}$

$ = {\,^{2n + 1}}{C_0} + {\,^{2n + 1}}{C_1} + {\,^{2n + 1}}{C_2} + ... + {\,^{2n + 1}}{C_{n - 1}} + {\,^{2n + 1}}{C_n}$

$ = {1 \over 2}\left[ {{{(1 + 1)}^{2n + 1}}} ight]$$ = {1 \over 2}[{2^{2n + 1}}] = {2^{2n}}$.

A set contains $2n + 1$ elements. The number of subsets of this set containing more than $n$ elements is equal to

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