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What is the rule for the numbers 1; 2; 4; 7; 11; 16​

1 Answer

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Answer:

n²+n+2

Explanation:

1)Find the difference between the numbers.

Difference= +1,+2,+3,+4,+5

2)Find the second difference between the first differences.

Difference= +1 each time

2 differences=Quadratic sequence

3)Quadratic Sequence Equation= an²+bn+c

Find the values of a, b and c by using these terms:

a (bottom)

2a+b (middle)

a+b+c (top)

4)Substitute values into equation

a=1 b=1 c=2

n²+n+2

What is the rule for the numbers 1; 2; 4; 7; 11; 16​-example-1
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