The sum of 'n' terms of an arithmetic sequence is 4n2+3n. What is the first term, the common difference, and the sequence?

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Answer:

Step-by-step explanation:

If the 2 is an exponent, it should be indicated with a circumflex:  4n^2+3n.

What is the first term?

a₁ = S₁ = 4·1² + 3·1 = 7

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What is the common difference?

a₁ + a₂ = S₂ = 4·2² + 3·2 = 22

a₂ = 22-a₁ = 15

common difference d = a₂ - a₁ = 8

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What is the arithmetic sequence?

The nth term is 7+(n-1)d = 7+(n-1)8 = 8n-1.

a₁ = 8·1-1 = 7

a₂ = 8·2-1 = 15

a₃ = 8·3-1 = 23

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