Question

How do you find the sum of `Sigma [(i-1)^2+(i+1)^3]` where i is [1,4]?

Answer 1

`238`

Explanation:

`sum_(i=1)^4 [(i-1)^2+(i+1)^3]`

`=sum_(i=1)^4 (i^2-2i+1+i^3+3i^2+3i+1)`

`=sum_(i=1)^4 (i^3+4i^2+i+2)`

`=((4*5)/2)^2+4*(4*5*9)/6+(4*5)/2+2*4`

`=238`