SOLUTION: The pth term of an AP is (3p-1)/6. The sum of the first n terms of the AP is?

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Question 863642: The pth term of an AP is (3p-1)/6. The sum of the first n terms of the AP is?
Answer by stanbon(75887) About Me  (Show Source):
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The pth term of an AP is (3p-1)/6. The sum of the first n terms of the AP is?
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Sum Formula: S(n) = (n/2)(a(1)+a(n)
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a(1) = (3-1)/6 = 1/2
a(n) = (3n-1)/6
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S(n) = (n/2)[(1/2)+(3n-1)/6]
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= (n/2)[(3+3n-1)/6]
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= (n/2)(3n+2)/6
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= (3n^2+2n)/12
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Cheers,
Stan H.
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