Question

Use summation notation to express the sum
2-1/2+1/8...+1/2048

Answer 1

looks like you are multiplying each term by \(\frac{1}{4}\) to get the next

Answer 2

also the signs alternate
maybe try \[\sum_{k=0}^n2\times (-\frac{1}{4})^k\]

Answer 3

oh i guess you have to stop at \(\frac{1}{2048}\) right?

Answer 4

you could try
\[\sum_{k=0}^62\times (-\frac{1}{4})^k\]

Answer 5

i am sure there are other ways to do it

Answer 6

Okay thank you