Question

Find the sum of the finite geometric series. 3-9+27-81+243-729+2187-6561+19683-59049

Answer 1

for the finite G series the formula is [a(1-r^(n-1)]/1-r

Answer 2

a=3, r=-3 , n= 10

S(n) = a(1-r^(n) ) / (1-r) sub etc lol

Answer 3

\[\frac {a(1-r^n) }{1-r}\]

Answer 4

:( again mistake

Answer 5

yes right :)

Answer 6

wait min

Answer 7

you might be right, yeh, thought it looked a little strange

I wikipedia it, and it is a(1-r^(n-1) ) / (1-r)

Answer 8

oh let me check

Answer 9

hmm no you were right before

Answer 10

no I was correct firsdt time

Answer 11

yes , just went to check a high school maths study guide lying around

Answer 12

yes the first 1 is right

Answer 13

damm wikipedia, its usually a good resource for maths

Answer 14

but wikipedia shows the same formula u wrote at the first place :)

Answer 15

I can seem to find it, ahh I am bit tired

Answer 16

cant*

Answer 17

i am lost now lol

Answer 18

yes its for sure :)

Answer 19

\[\frac {a(1-r^n)}{1-r}\]


sub in a=3, r=-3, n=10

Answer 20

3[1-(-3)^10]/1-3
=3[1-3^10]/2

Answer 21

so is the answer 1536?

Answer 22

???

Answer 23

u calculated it?does it come 1536?

Answer 24

yes that is what i got, is that what you got?

Answer 25

i dint calculate :)

Answer 26

oh ok... but does that make sense? my answer???

Answer 27

sure :)

Answer 28

lol ok thank you