Question

expand 7 (sigma symbol) n=3 (n+4)

Answer 1

\[\sum_{n=3}^7n+4\]?

Answer 2

put \(n=3\) and get \(3+4=7\)
then put \(n=4\) and get \(4+4=8\) etc
then add them up

Answer 3

in other words
\[7+8+9+10+11\]