Express the following sum in closed form (without using a summation symbol and without using an ellipsis . . . ): $\sum _ { k = 0 } ^ { n } \left( \begin{array} { l }
n \
k
\end{array} \right) 7 ^ { k }$

Question

Express the following sum in closed form (without using a summation symbol and without using an ellipsis . . . ): $\sum _ { k = 0 } ^ { n } \left( \begin{array} { l } 
n \
k
\end{array} \right) 7 ^ { k }$

Quizplus · Accepted Answer

The Answer of Express the following sum in closed form (without using a summation symbol and without using an ellipsis . . . ): $\sum _ { k = 0 } ^ { n } \left( \begin{array} { l } 
n \
k
\end{array} \right) 7 ^ { k }$

Express the Following Sum in Closed Form (Without Using a Summation