3.-18,108,-648 find the next three terms

Fifth term: 3888. Sixth term: - 23320

Step-by-step explanation:

Notice that - 18 is 6 times the first term (3) : - 6 (3) = - 18. Next, 108 is the product of - 6 and - 18. Thus, the common ratio is - 6.

If a (1) is the first term and r is the common ratio, a formula for the nth term is

a (n) = a (1) * r^ (n-1).

Here, a (n) = 3 * (-6) ^ (n-1). As a check, let's determine whether this formula correctly predicts the 4th term (-648):

a (4) = 3 * (-6) ^ (4-1) = 3 * (-6) ^3 = 3 (-216) = - 648. Yes.

Thus, the 5th term is a (5) = 3 * (-6) ^ (5-1) = 3 * (-6) ^4 = 3 (1296) = 3888,

and

the 6th term is a (6) = 3 * (-6) ^ (6-1) = 3 * (-6) ^5 = - 23320.