Question

In the expansion of `(X+y)^(n)`, the coefficients of the 17th and the 13th terms equal. Find the numbher of term in the expansion
A. 18
B. 22
C. 28
D. 29

Answer 1

Correct Answer - D
The coefficient of the 17th is `""^(n)C_(16)`
The coefficeint of the 13th is `""^(n)C_(12)`
Given that the coefficients are equal.
`""(n)C_(16)=""^(n)C_(12)`
`n=16+12=28`
`:.` The number of terms in the expabnsion is `28+1=29`