Step-by-step explanation:
again, in a geometric sequence every term is created by mutilated the previous term by a constant factor.
-192 × f = 48
f = 48/-192 = -1/4
here it seems to be clear now that your teacher starts counting at a1 (and not a0).
a1 = -192
a2 = a1 × -1/4 = -192 × -1/4 = 48
a3 = a2 × -1/4 = a1 × -1/4 × -1/4 = -192 × 1/16 = -12
an = -192 × (-1/4)^(n-1)
a6 = -192 × (-1/4)⁵ = -192 × -1/1024 = 3/16
