Question

The middle term of the binomial expansion of $(a+b{)}^n$ is the $6^{th}$ term.Find the possible values of n,if n is even

• A. 8
• B. 9
• C. 10
• D. 11

Answer 1

The correct option is C

10

There can be two cases; n is even and n is odd

If n is even, then there will be only one middle term, which is $(\frac{n+2}{2}{)}^{th}$ term.

$\frac{n+2}{2}=6$

$\Rightarrow$ n + 2 = 12

$\Rightarrow$ n = 10