Question

Evaluate

Answer 1

\[\sum_{n=2}^{8} -(n-5)\]

Answer 2

@cshalvey

Answer 3

This notation would mean you start with N=2, and find all the values N=2 to N=8 using
-(n-5) and add them together. (Kinda like a "for"-loop if you take computer science)

So let's start:
When N=2 -> -(2-5)= -(-3) = 3
When N=3 -> -(3-5)= -(-2) = 2
When N=4 -> -(4-5)= -(-1) = 1
When N=5 -> -(5-5)= -(0) = 0
When N=6 -> -(6-5)= -(1) = -1
When N=7 -> -(7-5)= -(2) = -2
When N=8 -> -(8-5)= -(3) = -3

Add all the numbers on the right up: 3+2+1+0+(-1)+(-2)+(-3)=0
Your answer is 0! :)