JEE Mains · Maths · STD 11 - 8. sequence and series
If \(^n{C_4},{\,^n}{C_5},\) and \({\,^n}{C_6},\) are in \(A.P.,\) then \(n\) can be
- A \(9\)
- B \(14\)
- C \(11\)
- D \(12\)
Answer & Solution
Correct Answer
(B) \(14\)
Step-by-step Solution
Detailed explanation
\(2.{\,^n}{C_5}{ = ^n}{C_4}{ + ^n}{C_6}\) \(2.\frac{{\left| n \right.}}{{\left| {5\left| {n - 5} \right.} \right.}} = \frac{{\left| n \right.}}{{\left| {4\left| {n - 4} \right.} \right.}} + \frac{{\left| n \right.}}{{\left| {6\left| {n - 6} \right.} \right.}}\)…
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