Question

Question 3 (1 point)

Which is the explicit rule for the geometric sequence?
10, -30, 90, -270, ...

Answer 1

The rule for this question should be an=10*(-3)^(n-1)

Explanation:

Because 10, -30, 90, and -270 divide (for example -30/10, 90/-30 and -270/90 which means the ratio equals -3) To find the ratio, you must divide by its previous term.

Then, the equation for the ratio would be a1 (first term in the sequence) multiplied by the ratio, then to the power of the number subtracted by 1. an=a1*r^(n-1) This is the formula to find the nth term of a geometric sequence.

Hope this helped!