Which of these satisfies a1+a2=6a_1 + a_2 = 6a1+a2=6 and a2+a3=12a_2 + a_3 = 12a2+a3=12 for a geometric sequence?
r=1r = 1r=1
a1=2a_1 = 2a1=2
r=2r = 2r=2
r=−2r = -2r=−2