Question

Write the recursive formula for the geometric sequence.

a1 = -2 a2 = 8 a3 = -32
A. an = -4 + an-1

B. an = -2 + an-1

C. an = -2 • an-1

D. an = -4 • an-1

Answer 1

Notice that \(a_2=8=(-4)\times(-2)=-4a_1\), and that \(a_3=-32=(-4)\times(8)=-4a_2\). See the pattern?