Question 132279
1st:5 2nd:14 3rd:27 4th:44 5th:65 State the 10th and 20th term.
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Taking successive differences you get: 
14-5 = 9 ; 27-14 = 13; 44-27 = 17; 65-44 = 21
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Taking successive differences again you get:
13-9 = 4; 17-13 = 4; 21-17=4
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Since the 2nd differences are a constant number, the pattern is quadratic.
Using the points (1,5)(2,14)(3,27)(4,44)(5,65)
you can find the quadratic pattern is y = 2x^2+3x
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Then you can find f(10) = 230
and f(20) = 860
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Cheers,
Stan H.