Mark the correct alternative in the following :

If in the expansion of and , the ratio of the coefficients of second and third terms, and third and fourth terms respectively are equal, then n is


Given:




T2 ; T3





(1)



T3 ; T4





(2)


Equating both equations:



2(n+1)=3(n-1)


2n+2 = 3n-3


n=5

1