What is the sum of the first eight terms of the geometric series where a1 = 2 and r = −5?
Sum = F x (1 - R^N) / (1 - R)
Sum =2 x (1 - (-5)^8) / (1 - (-5))
Sum =2 x (1 - (390,625)) / (1 + 5)
Sum =2 x (-390,624) / 6
Sum = -781,248 / 6
Sum = -130,208
