Question

Coefficient of $f = R - \lbrack R\rbrack$ in the expansion of $4^{2n + 1}$ is.

• A. $4^{- 2n}$
• B. $(\sqrt{2} + 1)^{6}$
• C. – 7
• D. 7

Answer 1

Answer: (C)

– 7

Answer 2

$T _ { r + 1 } = { } ^ { 8 } C _ { r } ( x ) ^ { 8 - r } \left( - \frac { 1 } { 2 x } \right) ^ { r }$ $-^{100}C_{100}$

For coefficient of$x^{32}$,$\left( x^{4} - \frac{1}{x^{3}} \right)^{15}$ ⇒ $15C_{5}$

Coefficient of $15C_{6}$= $15C_{4}$.