High School

What is the sum of the first six terms of the geometric series?

2, -6, 18, -54, ...

A. -364
B. 364
C. 182
D. -182

Answer :

Final answer:

The sum of the first six terms of the geometric series is -364.

Explanation:

To find the sum of the first six terms of the geometric series, we can use the formula for the sum of a geometric series. The formula is given by:

  • Sum = (first term) * (1 - (common ratio)^(number of terms)) / (1 - (common ratio))

In this case, the first term is 2 and the common ratio is -3. Plugging in these values into the formula, we get:

  • Sum = 2 * (1 - (-3)^6) / (1 - (-3))
  • Sum = 2 * (1 - 729) / (1 + 3)
  • Sum = 2 * (-728) / 4
  • Sum = -364

Therefore, the sum of the first six terms of the geometric series is -364, which corresponds to option (a).