WBJEE · Maths · Binomial Theorem
Let \(n\) be a positive even integer. If the ratio of the largest coefficient and the 2nd largest coefficient in the expansion of \((1+x)^{n}\) is \(11: 10 .\) Then, the number of terms in the expansion of \((1+x)^{n}\) is
- A 20
- B 21
- C 10
- D 11
Answer & Solution
Correct Answer
(B) 21
Step-by-step Solution
Detailed explanation
Let the number of terms, \(n=2 \mathrm{m}\) Now, by condition \(\frac{\text { Largest coefficient in }(1+x)^{\circ}}{\text { Second largest coefficient in }(1+x)^{n}}=\frac{11}{10}\) (given) \(\Rightarrow\)…
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