If ${}^n{C}_{12}{=}^n{C}_6$ then ${}^n{C}_2 =$?

Important Questions on Binomial Theorem

MEDIUM

RRC Group D CBT

IMPORTANT

RRB Indian Railway Group 'D' Recruitment - General Mathematics>Chapter 6 - Binomial Theorem>Exercise 1>Q 45

The middle term in the expansion of ${\left(x - \frac{1}{x}\right)}^{18}$ is