Exercise 3.

Consider the sequence given by \(a_n = 2\cdot 5^{n-1}\text{.}\)

  1. Find the first 4 terms of the sequence.

    What sort of sequence is this?

    • arithmetic

    • geometric

    • neither

  2. Find the sum of the first 25 terms. That is, compute \(\sum_{k=1}^{25}a_k\text{.}\)

in-context