Duration: 2:48

7 views

0

Sum of the series
\[
\sum_{k=0}^{2 m}(-1)^{k}\left(\begin{array}{l}
n \\
2 m-k
\end{array}\right)\left(\begin{array}{l}
n \\
k
\end{array}\right)
\]
where \( \left(\begin{array}{l}n \\ r\end{array}\right)={ }^{n} C_{r} \), is
(a) \( (-1)^{m}\left(\begin{array}{l}n \\ m\end{array}\right) \)
(b) \( (-1)^{\mathrm{m}}\left(\begin{array}{l}n \\ 2 m\end{array}\right) \)
(c) 0
(d) \( \frac{(-1)^{m}}{m !}\left({ }^{n} P_{m}\right) \)
📲PW App Link - https://bit.ly/YTAI_PWAP
🌐PW Website - https://www.pw.live