What is the sum of the first thirteen terms in a geometric series with a1=−3 and r=4?

The sum of the first 13 terms of the sequence is -67,108,863.

Step-by-step explanation:

Sum of the first n terms of a geometric sequence:

The sum of the first n terms of a geometric sequence, with first term and ratio r, is given by:

In this question:

Sum of the first 13 terms:

The sum of the first 13 terms of the sequence is -67,108,863.

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step-by-step explanation:

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