Question

How is the sum expressed in sigma notation? 1/64+1/16+1/4 + 1 + 4

Answer 1

9514 1404 393

Answer:

  sum = ∑[n=1,5] 4^(n-4)

Step-by-step explanation:

First of all, you need to be able to describe the n-th term.

Here, we  have ...

  term #: 1, 2, 3, 4, 5

  value: 4^-3, 4^-2, 4^-1, 4^0, 4^1

That is, the exponent of 4 is 4 less than the term number. So, the n-th term is 4^(n-4). The sum of the 5 terms shown is then ...

  $\displaystyle sum=\sum_{n=1}^5{4^{n-4}}$