Question

The coefficient of middle term in the expansion of $(1+x{)}^{10}$ is

• A. 10!/ 5!6!
• B. $10!/5{!}^2$
• C. 10! 5! 7!
• D. None of these

Answer 1

The correct option is B $10!/5{!}^2$

$(1+x{)}^{10}$

The middle term will be

${}^{10}{C}_5{x}^5$

coefficient is ${}^{10}{C}_5$

$=\frac{10!}{5!5!}=\frac{10!}{(5!{)}^2}$