JEE Mains · Maths · STD 11 - 7. binomial theoram
Let \( S=\frac{1}{25!}+\frac{1}{3!23!}+\frac{1}{5!21!}+. \dots \) up to 13 terms. If \( 13S=\frac{2^{k}}{n!} \) where \( k\in N \), then \( n+k \) is equal to
- A 51
- B 52
- C 49
- D 50
Answer & Solution
Correct Answer
(C) 49
Step-by-step Solution
Detailed explanation
\(\frac{1}{26!}\left(\frac{26!}{25!1!}+\frac{26!}{3!23!}+\frac{26!}{5!21!}+\ldots . .+13\right.\) terms \()\)…
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