Question

Write an explicit equation for the following
sequence:

4/7,-4, 28, -196, 1372, ...

Answer 1

a_n = (4/7)(-7)^(n - 1)

Explanation:

a1 = 4/7 = 4/7 × 1 = (4/7)(-7)^0

a2 = -4 = 4/7 × (-7) = (4/7)(-7)^1

a3 = 28 = 4/7 × (-7)(-7) = (4/7) × (-7)^2

etc.

a_n = (4/7)(-7)^(n - 1)