Question

The sum of the coefficients in the expansion of $(1-x{)}^{10}$ is

• A. $0$
• B. $1$
• C. $10^2$
• D. $1024$

Answer 1

Answer: (A)

${\left(1-x\right)}^{10}=1-{}^{10}{C}_{1}x+{}^{10}{C}_2{x}^2-{}^{10}{C}_3{x}^3+...$
$...+{}^{10}{C}_{10}{x}^{10}$
$\therefore$ Sum of coefficients $=1-{}^{10}{C}_1+{}^{10}{C}_2-{}^{10}{C}_3+...+{}^{10}{C}_{10}$
$=0$