Question

Sigma Notation...are these correct? (Please check answers)?

Answer 1

120 for first one

Answer 2

-5k + 20, k = 3 to 6

let u = k-3, therefore k = u+3

-5(u+3) + 20, u = 0 to 3

-5u -15 + 20, u = 0 to 3

-5u +5, u = 0 to 3

5 +0 -5 -10

Answer 3

2 one is correct

Answer 4

do you see why you missed the first one?

Answer 5

Thank you @danish071996 !

Answer 6

@amistre64 I'm still confused on the first, I still have the answer as 60?

Answer 7

did you pull out a 2 or a 2^2 ? im assuming you used the formulas

Answer 8

Oh I may have squared wrong! I just tried differently and got 4 + 16 + 36 + 64 = 120

Answer 9

Thank you @amistre64 : ) My mistake

Answer 10

yep, thats better :)

Answer 11

wlcm jnov