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The formula for any geometric sequence is a n = a 1 · r n - 1 , where a n represents the value of the nth term, a 1 represents the value of the first term, r represents the common ratio, and n represents the term number. What is the formula for the geometric sequence 4, 8, 16, 32, ...?

an = 32 · 2n - 1
an = 2 · 4n - 1
an = 4 · (1/2)n - 1
an = 4 · 2n - 1

User Pagep
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2 Answers

8 votes
B bc 2 goes through everything and the same thing as 4
User Moudiz
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7 votes

Answer:

Step-by-step explanation:instead, try making the subscripts and superscripts stand out:

n-1

a = a * r

n n-1

Believe me, it's worth the extra work to do this!!

Given the sequence -3, -6, -12, -24, you can easily see that the first term,

a is -3. The common factor is 2. Note how (-3)*2=-6, and so on.

1

So, a = -3 and r=2.

1

So the formula for this geometric sequence is

n-1

a = -3*2

n

User Shayki Abramczyk
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