Question

Express the series -27 + 9 - 3 + 1 - ... using sigma notation?

Answer 1

@amistre64 can you please help me?

Answer 2

well, any thoughts to start with?

Answer 3

i would guess that its infinity..

Answer 4

not 3

Answer 5

well, the index goes to infinity, so we can toss that one out

what is our first term?

Answer 6

-27?

Answer 7

i can read it just as well as you, not sure about the question mark ...

-27 is what we want when k=0

which of the options gives us this?

Answer 8

-3

Answer 9

-3(0) = -27 , i dont think so

Answer 10

0

Answer 11

oops

Answer 12

is it 27?

Answer 13

what is (-1/3)^0 ?

Answer 14

1

Answer 15

then our firt term is either :

-27(1) = -27

or

27(1) = -27

Answer 16

of course -27(1) = -27

Answer 17

then what do we pick?

Answer 18

C.

Answer 19

good :)

Answer 20

that was easier than I thought. Thank you!

Answer 21

yep ..