Find the first 4 terms and the 8th term of the recursively-defined sequence.

4. v1 = 0.75 and vn = (-2)vk-1 for n>1

A. 0.75, 1.5, -3, 6; -192

B. -1.5, -3, -6, -12; 192

C. -1.5, -3, -6, -12; -192

D. 0.75, 1.5, 3, 6; -192

E. 1.5, 3, 6, 12; 192

F 0.75, -1.5, 3, -6; 192

Can you also show some of the steps, if possilbe? I'm not sure where to begin.

2 answers

the terms will be .75 * alternating powers of 2

v_k =
.75 * (-1)^k-1 * 2^(k-1)
.75(1 -2 4 -8 16 -32 64 -128)
so, looks like (F) with a typo.
Thanks Steve!