For (x + y)^n:

• If n is even: One middle term = $T_{n/2 + 1}$
• If n is odd: Two middle terms = T_{$\frac{n+1}{2}$} and T_{$\frac{n+3}{2}$}

The middle term typically has the largest absolute value when x and y have comparable magnitudes, and always involves the largest binomial coefficient C(n, floor$\frac{n}{2}$).

Example: In (1 + x)^6, middle term is $T_4$ = C(6,3)$x^3$ = 20$x^3$. In (1 + x)^7, middle terms are $T_4$ = C(7,3)$x^3$ = 35$x^3$ and $T_5$ = C(7,4)*$x^4$ = 35$x^4$.