Question

I solved one of these sigma notations and had Reiny check it in an earlier post but this one totally befuddles me-
Which of the following terms would not be in the series generated by the expression: 5
Signma symbol (k^2-5k+2)
k=2

the choices are 2, -2, 4 or -4If you could even just provide a starting point- we are just learning this and I'm not doing too great right now-thank you but I'm trying

Answer 1

the 5 should be on top then the signma symbol in middle and the k=2 on the bottom with the equation (k^2 -5k+2) to the right of all of it

Answer 2

It simply means subbing in k=2, k=3 ... k=5 into the expression and adding up the results
that is.

= (2^2 - 5(2) + 2) + (3^2 - 5(3) + 2) + ... + (5^2 - 5(5) + 2)
= -4 + (-4) + (-2) + 2

I can see why you would be confused, since none of your choices are NOT a term generated by the expression.
Misprint in the question?
Question is faulty?

Answer 3

No the way I typed is is the way it is written--
5 on top, sigma symbol in middle and k=2 on bottom with the equation (k^2-5k+2) to the right and the answers are possible:
4, -4, 2, -2
I'm not sure if I see (4) used above when you substituuted-is that the one not generated??

Answer 4

of course!
You are right, I guess I can't read my own typing

4 is it!

Answer 5

Thank you