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

a1 = -2
a2 = 8 = -4 x -2 = -4a1
a3 = -32 = -4 x 8 = -4a2

Therefore, an = -4 * an-1

Answer 2

an = -4 + an-1
This is the answer, Hope it helps!