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Write a recursive rule for the sequence: 2, 8, 32, 128, 512,. . . (NO LINKS!!!)​

1 Answer

3 votes

Answer:

a1 =2

an = an-1 * 4

Explanation:

We can tell this is geometric by the way it increases

To find the common ratio, take the second term and divide by the first term

8/2 =4

Check to make sure

2*4=8

8*4 =32

32*4 =128

The recursive formula is

a1 = the first term

an = an-1 *r

a1 =2

an = an-1 * 4

User Khayam Gondal
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