Question

How do you write the summation notation for: 4 - 24 + 144 - 864 + ... ?

Answer 1

\[\sum_{k=0}^{\infty}(-1)^n*4*6^n \]

Answer 2

@Loser66 is another way to right that 4(-6) ^n-1 ?

Answer 3

you want the sequence start from n =1?

Answer 4

@Loser66 no, n=0

Answer 5

\[\sum_{n=1}^{\infty}(-1)^{n-1}*4*6^{n-1}\]

Answer 6

those are 2 ways to write it out , first starts from n=0, second starts from n=1 . I know what you mean, wait.

Answer 7

@Loser66 Thank you!!! can I ask one more?!
for: -3 + 6 + 15 + 24 + ... + 132

Answer 8

\[\sum_{n=0}^{15}(-3)+9n\]

Answer 9

@Loser66 thank you so much!

Answer 10

yw