Find the number of middle terms in the expansion of (a+b)21
In the expansion of (a+b)n, if n is odd, there are two middle terms, which are (n+12)th and (n+12+1)th terms.
Number of middle terms in the expansion of (a+b)21 is:
Find the number of middle terms in the expansion of (a+b)20.
Number of middle terms in the expansion of (a+b)20 is: