Question

Find the middle terms in the expansion of (x⁴ - 1/x³)¹¹

Answer 1

Here, a  = x⁴, b = -1/x³, n = 11

Now, n is odd

\(\therefore\) Middle terms are t₆ and t₇; for which r = 5 and r = 6 respectively.

We have t_r+1 = ⁿC_r a^n-rb^r

= 462x²

^{\(\therefore\)} Middle terms are -462x⁹ and 462x².