Question

What is the recursive formula for 6,-2,-10,-18

Answer 1

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Answer:

• a(1) = 6
• a(n) = a(n-1) -8

Explanation:

The ratio of the first two terms is -2/6 = -1/3. Their difference is -2-6 = -8.

The ratio of the next two terms is -10/-2 = 5. Their difference is -10-(-2) = -8.

The ratio is not common, but the difference is. This is an arithmetic sequence with a common difference of -8. Its first term is 6, so the recursive formula is ...

a(1) = 6

a(n) = a(n-1) -8