Question 13 (Essay Worth 8 points) Write the sum using summation notation, assuming the suggested pattern continues.

3, -12, 48, -192, + …

Is this sequence arithmetic or geometric? Explain your answer.

9514 1404 393

  geometric sequence

Step-by-step explanation:

The terms of the sequence have a common ratio of -12/3 = -4, so the sequence is geometric. The general term is ...

  an = 3(-4)^(n-1)

so the sum can be written as ...

(Note the summation starts at n=0, corresponding to a first term of 3.)

answer:   x = 3 + √11     and     x = 3 - √11

step-by-step explanation:

x² - 6x + 9 = 11

(x - 3)² = 11

x - 3 = ±√11

    x = 3 ± √11

x = 3 + √11     and     x = 3 - √11