Question

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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Answer 1

$\frac{n}{2} (2a + (n - 1)d)$

Answer 2

Answer:

Step-by-step explanation: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