what is the value of the following sigma notation?

Question

 5

 ∑   (i^2 -3)

i=2

Answer 1

when i = 2, term is two squared minus 3, i.e. 1

when i = 3, term is 6

when i = 4, term is 13

when i = 5, term is 22

 

now sum these.

Answer 2

If  (a_i = i² - 3), the value is

 

a₂ + a₃ + a₄ + a₅

 

 

This should give you a hint.