Question

Write the sum using summation notation, assuming the suggested pattern continues. -10 - 2 + 6 + 14 + ... + 110

Answer 1

So what's the difference between each term?

Answer 2

8?

Answer 3

Yep , so you start with 8n. we can start with n=0.
so 8(0) = 0, but we need first one to be -10

Answer 4

So 8n-10

Answer 5

So n starts with 0, now what's left is what n is for 8n-10 to be equal to 110, do you know?

Answer 6

15?

Answer 7

Right.

Answer 8

So you can write it like this:
\[\Large \sum_{n=0}^{15} 8n-10\]

Answer 9

Okay cool, that was my answer choice but I wasn't sure ((: thanks!

Answer 10

welcome!