Question

Find the first six terms of the sequence.
a1 = -1, an = 2 • an-1 (7 points)
Select one:
a. -2, -4, -8, -16, -32, -64
b. -1, -2, -4, -8, -16, -32
c. -1, -2, 0, 2, 4, 6
d. 0, 2, -2, 0, 2, 4

Answer 1

It's b. -1,-2,-4,-8,-16,-32
because 
$a_n=2a_{n-1} \mbox{ where } a_1=-1.\\ So\\ a_2=2a_1=-2\\ a_3=2a_2=-4\\ a_4=2a_3=-8\\ a_5=2a_4=-16\\ a_6=2a_5=-32.$

Answer 2

The answer to this is B.  " -1 , -2 , -4, - 8, -16 , -32