Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. If $1+\displaystyle\sum_{ r =1}^{ n }{ }^{ n + r } C _{ r }={ }^{25} C _{13}, n \in N$, then the value of $n$ equals

Binomial Theorem

Solution:

$1+{ }^{n+1} C_1+{ }^{n+2} C_2+\ldots . .+{ }^{n+n} C_n={ }^{25} C_{13} \Rightarrow{ }^{1+2 n} C_n={ }^{25} C_{13} \Rightarrow n=12$