Question

The coefficient of $x^{19}$ in the expression $(x-1)\left(x-2^2\right)\left(x-3^2\right)$ $\left(x-20^2\right)$ must be

• A. 2870
• B. 2800
• C. $-2870$
• D. -4100$

Answer 1

Answer: (C)

Co-efficient of $x^{19}$ in expression $=-\left(1^2+2^2+3^2+\dots \dots ..+20^2\right)=-2870$