Use the explicit or recursive formulas for the geometric sequence 45,135,140,1215,3645... To the sum of the first 9 terms of the sequence

Step-by-step explanation:

Given

Required:

The sum of the first 9 terms

We'll solve this question using the explicit formula:

Because it is a geometric sequence, we first calculate the common ratio (r).

Let n = 2;

So, we have:

So, we have:

Explicitly, the sum of  n terms of a geometric sequence is:

The formula becomes:

Hence, the sum of the first 9 terms is 442845

a.

step-by-step explanation:

step 1 distribute 2 to every term in the parentheses

step 2 add 10 on both sides of the equal sign

answer: idk

step-by-step explanation: