# Math Help - Sum

1. ## Sum

I have no idea how to solve this

20
∑ (i^3 + 3i^2 + 2i)
i=1

find the sum

2. Originally Posted by bookworm25
I have no idea how to solve this

20
∑ (i^3 + 3i^2 + 2i)
i=1

find the sum
$= \sum_{i = 1}^{20} i^3 + 3 \sum_{i = 1}^{20} i^2 + 2 \sum_{i = 1}^{20} i$ and each of the summations can be calculated using well known formulae eg. see here Some special sums