This week in Pre-calculus 11 I learned about geometric sequences and how to use the formulas to isolate variables. In a geometric sequence each term is multiplied by a constant, known as a common ratio.

My geometric sequence:

3, 12, 48, … 49152

from this sequence we know:

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• r = 4

To find r we use the formula, , so:

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• r = 4

In this sequence we are trying to find what n is. To do that we would use the general formula used to find :

, we then input all information that we already know.

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we then need to divide everything by 3 to make it easier for us to isolate n.

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To then find n you keep multiplying 4 by different powers until it matches the value of divided by . In this case we would multiply 4 by different powers until we get 16384.

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If we know tat the power is 7 then that means that we know, 7 = n -1. We now know that n = 8 because 8 – 1 = 7.