Answer:
147
Step-by-step explanation:
The ∑ symbol means sum the term inside 4n + 1 from n = 2 to n = 8
Substitute n = 2, 3, 4, 5, 6, 7, 8 into the expression and sum the results , that is
4(2) + 1 + 4(3) + 1 + 4(4) + 1 + 4(5) + 1 + 4(6) + 1 + 4(7) + 1 + 4(8) + 1
= 9 + 13 + 17 + 21 + 25 + 29 + 33
= 147
