MCQ
Expand the following binomials: $(x - 3)^5$
- A$ x^5+25 x^4+90 x^3-270 x^2+405 x-243 $
- B$ x^5-15 x^4+90 x^3-270 x^2-405 x-243 $
- C$ x^5-15 x^4+80 x^3-270 x^2+405 x-243 $
- ✓$ x^5-15 x^4+90 x^3-270 x^2+405 x-243 $
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
$\operatorname{det}\left[\begin{array}{cc}\sum_{k=0}^n k & \sum_{k=0}^n{ }^n C_k k^2 \\ \sum_{k=0}^n{ }^n C_k k & \sum_{k=0}^n{ }^n C_k 3^k\end{array}\right]=0$, holds for some positive integer $n$. Then $\sum_{k=0}^n \frac{{ }^n C_k}{k+1}$ equals